# Training pipeline audit — plateau escape, stability, normalization, capacity

Date: 2026-08-09. Scope: everything between the feature vector and the deployed checkpoint —
input normalization, derived topology, optimizer/learning-rate mechanics, the era loop's
correction mechanisms (checkpoint restore, eta decay, plateau ladder, shadow EMA), and the
selection/deploy gates. Every claim below carries a file:line reference; nothing is quoted
from memory.

---

## 0. Verdict in one paragraph

The pipeline is structurally sound and unusually well-defended (purged OOS split, logit-adjusted
loss, family-wise deploy gate, checkpoint restore on regression). The instability you see between
eras has three real, fixable contributors: **(1)** training is pure batch-size-1 online Adam, so
per-era weight trajectories are intrinsically noisy; **(2)** the learning-rate machinery operates
inside a 3x total dynamic range (1e-4 … 3e-4), so the plateau ladder's "warm restart" is a no-op
whenever eta is already at its ceiling — which is exactly the state a non-regressing plateau is in;
**(3)** the pass-2 shuffle uses MQL5's 15-bit `MathRand()`, which makes the Fisher-Yates provably
non-uniform on any era with more than 32,768 queued samples (every full-history H1 run). Fixing
these will make training *smoother and more monotone*. What they will not do is make OOS accuracy
climb "better and better": the repo's own measurements (noise-floor MI verdict, lag-profile verdict,
26 classic-pattern models at chance on 178k bars) say the directional information in these features
is at or below the noise floor. A neural net does not find patterns where there is no mutual
information; it finds patterns where nobody *looked*, which is a different thing. The honest
formulation of your goal is: IS error should fall monotonically (it can), OOS should rise to the
data's information ceiling and hold there stably (it can), and the family-wise gate decides whether
that ceiling is tradeable (so far it has said no).

---

## 1. Direct answers to your questions

### "We use Adam as the main optimizer and switch to SGD for fine-tuning — right?"

**No.** There is exactly one optimizer per model, chosen by the `TrainingOptimizer` input
(default `ADAM`, [Variables/Inputs.mqh:210](../Variables/Inputs.mqh#L210)), and it runs for the
whole life of the model. An Adam→SGD switch *used to exist* ("replay-only optimizer override")
and was removed on 2026-07-28 for good reason: it forced the entire net to SGD during pass 2,
and pass 2 is the **only** place `backProp()` runs — so "Adam with SGD fine-tuning" was in fact
"SGD at Adam's learning rate, always", with Adam's moments never updated. The removal note is at
[Training.mqh:680-689](../Expert/AIBase/Training.mqh#L680-L689). Do not reintroduce a switch;
the literature on optimizer switching (SWATS) shows mixed results, and this codebase has already
been burned once by a half-switched optimizer.

### "Should we play with learning rate and momentum when we keep regressing?"

The pipeline already adjusts the learning rate on regression — but inside a range so narrow the
adjustments barely do anything. Current mechanics:

| Mechanism | Trigger | Effect | Where |
|---|---|---|---|
| eta decay | selection score drops >5pp below best (`ETA_DECAY_REGRESSION_PCT`) | best checkpoint restored, `eta *= 0.7`, floor 1e-4 | [Training.mqh:1545-1554](../Expert/AIBase/Training.mqh#L1545-L1554) |
| recovery bump | new best era | `eta /= 0.7`, cap at ceiling | [Training.mqh:1482](../Expert/AIBase/Training.mqh#L1482) |
| warm restart | 8 / 16 eras with no new best (plateau stages 1, 2) | `eta = m_etaCeiling` | [Training.mqh:1588-1602](../Expert/AIBase/Training.mqh#L1588-L1602) |
| terminal | 24 eras with no new best (stage 3) | deploy best checkpoint, stop | [Training.mqh:1604-1662](../Expert/AIBase/Training.mqh#L1604-L1662) |

Constants: ceiling = `AdamLearningRate` = 3e-4 ([AI/Network.mqh:68](../AI/Network.mqh#L68)),
`ETA_MIN` = 1e-4, `ETA_DECAY_FACTOR` = 0.7
([ExpertSignalAIBase.mqh:295-297](../Expert/ExpertSignalAIBase.mqh#L295-L297)).

**Finding F2 (high impact): the plateau ladder's only escape is frequently a no-op.**
eta starts at the ceiling and only ever *leaves* the ceiling via the regression-decay branch.
A run that plateaus *without* a >5pp regression therefore sits at eta == ceiling, and both
"warm restarts" assign the value eta already has. In that state the ladder is not an escape
mechanism at all — it is a 24-era countdown to deploy. Even in the best case (eta floored at
1e-4), the restart is a 3x kick; SGDR-style restarts that actually relocate a model typically
span 10-100x. Additionally, escaping a basin generally requires a rate *larger* than the one
that settled into it — restoring the original rate revisits the same basin.

**Momentum:** `AdamBeta1` = 0.9 / `AdamBeta2` = 0.999, book defaults
([AI/Network.mqh:68-77](../AI/Network.mqh#L68-L77)); bias correction is implemented correctly
per-neuron (`lt = eta*sqrt(1-b2^t)/(1-b1^t)`,
[NeuronOCLBase.mqh:564,613](../AI/Impl/NeuronOCLBase.mqh#L613)). Hand-tuning beta1 was already
tried (0.8 experiment) and correctly reverted. The momentum problem is not the constants — see F3.

**Finding F3 (medium): checkpoint restore keeps stale Adam moments.**
`CaptureWeights()/RestoreWeights()` snapshot weights only — documented deliberately at
[AI/Network.mqh:686-689](../AI/Network.mqh#L686-L689). After a restore, the very next updates are
driven by first/second moments accumulated *along the rejected trajectory*, i.e. the optimizer
immediately pushes the restored weights back toward the state that just got rolled back. The delta
clip and decayed eta bound the damage but don't remove the direction. This is a plausible direct
cause of the "restore → regress again → restore again" oscillation you're watching. Zeroing the
moment buffers (and the per-neuron `t` counters) on restore — and on plateau warm restarts — is
cheap and is standard practice in Adam-with-restarts setups.

### "Do we have enough neurons and layers?"

The shape is *derived from the data*, not configured, and the derivation is deliberate about being
small: the first dense layer gets at most **one weight per in-sample bar**
([Topology.mqh:809-841](../Expert/AIBase/Topology.mqh#L809-L841)), snapped down a
{16,32,64,…,1024} ladder; depth comes from a geometric taper to the output
([Topology.mqh:669-689](../Expert/AIBase/Topology.mqh#L669-L689)); conv filters = half the
receptive-field window snapped to {4..32}; LSTM hidden solves `4H(H+in+1) ≤ isBars`
([Topology.mqh:771-805](../Expert/AIBase/Topology.mqh#L771-L805)).

Two honest observations:

- **Capacity is not why training plateaus.** More neurons buy IS fit. The OOS ceiling is set by
  how much label-relevant information the features carry, and the project's own measurements put
  that at/near the noise floor for direction ([[project_lag_profile_verdict]],
  [[project_mi_noise_floor_verdict]], [[project_classic_patterns_no_edge]]). A bigger net finds
  the noise faster.
- **Finding F6 (low-medium): with the full default feature set the first layer is pinned at its
  16-unit floor.** ~60+ features/bar × 20 bars ≈ 1,200+ inputs; at ~25-30k in-sample bars the
  budget `isBars/(inputWidth+1)` lands near or below 16, so the derived width bottoms out and the
  warning at [Topology.mqh:833-839](../Expert/AIBase/Topology.mqh#L833-L839) may already be firing.
  Check the startup `config -` line. If it reads "N dense from 16 units", the honest options are
  (a) prune feature groups the research track has already measured as edge-free, which widens the
  budget per input, or (b) accept the pinch — *not* raise the budget: 1 param/sample is already
  generous for this signal-to-noise regime.

---

## 2. Bug found

**Finding F1: biased Fisher-Yates — `MathRand()` is 15-bit.**
[Training.mqh:699](../Expert/AIBase/Training.mqh#L699): `int sJ = MathRand() % (sIdx + 1);`
MQL5's `MathRand()` returns 0..32767. For every `sIdx ≥ 32768` the modulo is the identity, so
`sJ` is uniform on [0, 32767] only: a slot in the upper region can never swap with another upper
slot, and each upper element gets exactly one forced exchange with the lower region. For
`sIdx` just under 32768 there is ordinary modulo bias. The queue holds one entry per IS bar
(every bar queued exactly once, [Training.mqh:616-625](../Expert/AIBase/Training.mqh#L616-L625)),
and the training window is *all available history* — an H1 symbol easily exceeds 32,768 IS bars,
so the shipped configuration hits this every era. The shuffle exists precisely to break the
correlated same-class gradient runs documented at the `MAX_WEIGHT_DELTA` comment
([AI/Network.mqh:350-356](../AI/Network.mqh#L350-L356)); a non-uniform shuffle partially
re-admits them, era after era, in the same pattern (the bias is deterministic in structure).

**Fix (small):** compose a 30-bit value — `int r30 = (MathRand() << 15) | MathRand();` then
`sJ = r30 % (sIdx + 1);` (or rejection-sample to kill the residual modulo bias — at 30 bits
against ~100k the residual is negligible). Same fix applies to
[AutoTune.mqh:455](../Expert/AIBase/AutoTune.mqh#L455) if its array can exceed 32k (check).

---

## 3. Why eras "visually regress" — the full causal list

1. **Batch-size-1 online Adam (F4, the big one).** One weight update per sample
   ([NeuronBatchNorm.mqh:60-63](../AI/NeuronBatchNorm.mqh#L60-L63) states it plainly: "pure online
   SGD - one weight update per sample, never a batched pass"). Gradient noise at batch 1 is maximal;
   the end-of-era weight state is a random variable with substantial variance, so consecutive eras
   genuinely differ even with identical data. Every defense in the file (delta clip, weight decay,
   shadow EMA, checkpoint restore) is compensating for this at the symptom level.
   **Literature-backed fix: gradient accumulation into mini-batches of 16-64.** Noise scales
   ~1/sqrt(B); B=32 cuts update variance ~5-6x, smooths the loss trajectory, makes Adam's second
   moment estimate meaningful, and typically *speeds up* wall-clock convergence (fewer, better
   steps). This is the single highest-impact stability change available. Implementation: accumulate
   output-layer gradients across B samples before calling the update kernels — the shuffle,
   logit-adjust and sample-weight machinery are all unaffected.
2. **Stale Adam moments after checkpoint restore (F3, above).**
3. **No-op warm restarts (F2, above)** — the ladder never actually perturbs a stuck run, so a run
   oscillates in the 5pp dead zone (no restore, no decay: [Training.mqh:1452](../Expert/AIBase/Training.mqh#L1452))
   until the timer expires.
4. **Batch-norm statistics move on every forward pass, including OOS scoring (F5).** Documented as
   deliberate ([NeuronBatchNorm.mqh:70-79](../AI/NeuronBatchNorm.mqh#L70-L79)): pass 3 scoring
   advances the EMA mean/variance, so (a) the OOS number partly measures BN drift rather than the
   trained function, and (b) the same weights score differently depending on what was scored
   before them. `SetBatchNormFrozen` already exists and is already used by
   `ValidateCpuInference` ([Persistence.mqh:243-246](../Expert/AIBase/Persistence.mqh#L243-L246))
   for exactly this reason. **Fix: freeze BN stats for the duration of pass 3** (and the OOS
   simulation walk), unfreeze after. This changes measurement only, not live behavior, and makes
   the selection metric a pure function of the checkpoint — which is what a metric that decides
   deployment should be.
5. **Part of the "regression" is measurement noise, by design.** The per-era selection score at
   ~11k directional calls has ~0.4pp standard error, more at low-coverage eras; the 5pp
   dead zone deliberately ignores oscillation inside it; and `dOosForecast` is a 10,000-sample EMA
   ([NetBuild.mqh:16](../AI/Impl/NetBuild.mqh#L16)) that carries momentum across eras. Two eras
   that "look" different on the chart (NMS arrows redraw per era) can be statistically identical.

---

## 4. Normalization audit — result: sound, two representation nits

- **Price-unit features:** ATR-normalized at source, with the rationale spelled out at
  [Features.mqh:477-488](../Expert/AIBase/Features.mqh#L477-L488). Correct and cross-symbol stable.
  Bars with no ATR or EMPTY_VALUE are rejected, not zero-filled.
- **Clamps:** every block clamps to single digits (±10 swing, ±5 volume, ±2 delta); one
  whole-bar sanitize gate zero-fills anything non-finite or >1e4
  ([Features.mqh:921-937](../Expert/AIBase/Features.mqh#L921-L937)) — this is the fix for the
  2026-08-02 BN NaN-latch and it is correctly placed. BN has its own 1e6 input bound and a
  1e-4 std floor ([NeuronBatchNorm.mqh:103-109](../AI/NeuronBatchNorm.mqh#L103-L109)).
- **Layer-level:** batch norm ON by default (window 1000), placed between dense pairs and before
  the head ([Topology.mqh:1072-1134](../Expert/AIBase/Topology.mqh#L1072-L1134)), which absorbs
  the remaining cross-family scale differences. EMA-form stats with cold-start bias ramp — correct
  for an online regime.
- **Nit N1: `EventCode` (and `StructuralPhase`) are categorical codes fed as ordinals**
  ([Features.mqh:886-890](../Expert/AIBase/Features.mqh#L886-L890)). The network is told event 9
  is "three times" event 3. A first dense layer can partially untangle this, but it wastes
  capacity the 16-wide entrance doesn't have. Options: one-hot the code (costs ~10-20 inputs —
  conflicts with F6), or collapse to the 2-3 axes that matter (event fired y/n, direction ±1,
  phase 1-5 as its own scaled scalar). Low urgency; do it with the next forced retrain, since it
  changes the input contract (fingerprint `WIN`-style version bump).
- **Nit N2:** heterogeneous natural ranges remain (RSI/100 in [0,1] vs ±10 clamps vs raw Wyckoff
  readings "with no natural range", [Features.mqh:922-923](../Expert/AIBase/Features.mqh#L922-L923)).
  With BN on this is mostly harmless; without BN it would matter. Fine as is *because* BN defaults on —
  note the coupling if BN is ever disabled for an experiment.

---

## 5. Loss / head / labels — audited, no defects found

Joint softmax+CCE gradient over sigmoid-bounded outputs with `CLASS_LOGIT_SCALE` 6.0 temperature
([NetForward.mqh:387-401](../AI/Impl/NetForward.mqh#L387-L401),
[AI/Network.mqh:366-377](../AI/Network.mqh#L366-L377)); logit adjustment applied backward-only with
per-era re-measured priors ([Training.mqh:340-345](../Expert/AIBase/Training.mqh#L340-L345)); label
smoothing 0.9/0.05/0.05 sums to 1.0; AdamW-style decoupled decay at 1e-3 with the 0.01-failure
history documented; per-step delta clip 0.1; saturation-derivative floor 1e-3. The bounded-head +
temperature design is unconventional but internally consistent, and the comments correctly forbid
unbinding the head without retuning the two constants calibrated against it
([Topology.mqh:1144-1162](../Expert/AIBase/Topology.mqh#L1144-L1162)). Leave this stack alone.

---

## 6. Prioritized action plan

| # | Change | Effort | Expected effect | Risk |
|---|---|---|---|---|
| 1 | **F1** 30-bit shuffle RNG ([Training.mqh:699](../Expert/AIBase/Training.mqh#L699)) | trivial | removes a deterministic bias present in every full-history era | none |
| 2 | **F4** mini-batch gradient accumulation (B≈32) in `backProp` | medium | largest stability win; smoother, likely faster convergence | moderate (touches update path; verify dW/W in situ per [[feedback_verify_in_situ_not_offline]]) |
| 3 | **F3** zero Adam moments + `t` on `RestoreWeights()` and on plateau warm restarts | small | stops restore→re-regress oscillation | low |
| 4 | **F2** give restarts amplitude: restart eta to 3-10x ceiling for a bounded number of eras (delta clip already bounds per-step damage), widen `ETA_MIN` to 1e-5; optionally cosine-decay within the cycle (SGDR) | small | turns the ladder into a real escape instead of a timer | low-moderate |
| 5 | **F5** freeze BN stats during pass-3 scoring + OOS sim | small | selection metric becomes a pure function of the checkpoint | none (measurement only) |
| 6 | **F6/N1** prune measured-dead feature groups; re-encode EventCode | medium | frees entrance capacity; cleaner representation | forces retrain (fingerprint bump) |

Order matters: do 1, 3, 5 together (cheap, independently safe), then 2, then 4 — because 4's effect
can't be evaluated while per-sample noise (2) dominates the era-to-era variance.

### Implementation status (2026-08-09, same day — compiled clean, 0 errors 0 warnings)

- **F1 DONE** — `ShuffleRandomIndex()` (30-bit) added in ExpertSignalAIBase.mqh, used by the pass-2
  queue shuffle (Training.mqh) and the MI-null block shuffle (AutoTune.mqh).
- **F3 DONE** — `CNet::ResetOptimizerState()` (NetWeights.mqh) + per-neuron-type overrides
  (dense/conv/LSTM/batch-norm, both OCL and legacy scalar hierarchies; `ZeroOptimizerBuffer()` in
  BufferDouble.mqh). Called on the mid-run regression restore, on every plateau warm restart, and on
  the deploy-time restore in FinalizeTrainRun (online learning continues from that net). Weights,
  BN running statistics, and gamma/beta are untouched — optimizer state only.
- **F2 DONE** — `PLATEAU_RESTART_BOOST 5.0`: restarts now jump eta to 5x the ceiling (1.5e-3) with a
  geometric anneal back to the ceiling over `PLATEAU_PATIENCE_ERAS` eras (SGDR-style bounded cycle),
  cleared early on any new best; `ETA_MIN` widened 1e-4 → 1e-5. Each restart also resets optimizer
  moments (F3), so the kick explores instead of replaying the plateau's momentum.
- **F5 DONE** — BN running statistics frozen for the whole pass-3 OOS scoring walk
  (`SetBatchNormFrozen(true/false)`), with a defensive unfreeze in FinalizeTrainRun for the
  stop-mid-pass path. The selection metric is now a pure function of the checkpoint. The OOS
  continual-learning *simulation* is deliberately NOT frozen — it evaluates live adaptive behaviour,
  where the moving statistics are part of what is being simulated.
- **F4 DONE** (second pass, same day). True mini-batch accumulation, `TRAIN_BATCH_SIZE = 32`.
  Design: the O(n²) outer product is native (two new kernels/exports per backend —
  `AccumulateWeightGrad`, `AccumulateWeightGradConv`, plus a generic `AccumulateBufferInto`), while
  the optimizer step is **host-side MQL5, shared by every tier** (`ApplyAccumToBlock`), so there is
  one Adam/SGD implementation instead of four that can drift. Both DLLs rebuilt. Notes:
  - The LSTM needs no outer-product kernel — by the update pass its `WeightsGradient` already holds
    the sample's full dW. It could *not* simply be left un-zeroed between samples, because
    `CPU_LSTMSeqBackward`/`DML_LSTMSeqBackward` **memset that buffer on entry**; hence the separate
    accumulator plus elementwise add.
  - Batch-norm's gamma/beta accumulate in host arrays, not new `BatchOptions` slots — `BN_OPT_STRIDE`
    is baked into every persisted `.nnw` via `getWeightsBN`.
  - Scoped to pass 2 only; `OnlineLearnStep` keeps immediate per-sample updates. Every save,
    checkpoint and scoring boundary calls `FlushBatch()`, which scales by the *real* sample count so a
    short trailing batch still takes a correctly-sized step.
  - Degrades, never fails: `CNet::BatchSize()` returns 1 (with a one-time log line) on a tier that
    cannot accumulate — an OpenCL device where the kernels didn't build, or the legacy scalar tier a
    DLL-free Market build can land on. Those train exactly as before.
  - **Verified offline**: `DirectML/batch_accum_check.cpp` (+ `build_accum_check.bat`) drives the real
    exports and compares against an independent reference. All pass, including the load-bearing one —
    at B=1 the accumulator equals the gradient the *shipped unbatched kernel* forms internally, to
    1.1e-16. That proves the math, **not** that a layer trains in the assembled net; the in-situ check
    is still the per-layer `dW/W` report on a real era.
- **F6 DONE, and the root cause was not what this report first said.** Confirmed from the deployed
  `.cfg` files that CONV, LSTM and HYBRID were *all* pinned at the 16-unit floor (64 features/bar ×
  20 bars = 1,280 inputs). But the fix is not pruning features: `ComputeFirstLayerWidth()` was
  budgeting against the **raw** input width even on topologies where a conv/LSTM front end has
  already reduced it — an LSTM hands the dense stack 64 values, not 1,280, so it was being charged
  ~20x its real fan-in. Now budgeted against the front-end output, and capped at that width so the
  first dense layer can never fan *out* (a shape `FrontEndConfigSummary` already flags as a defect).
  `InitNeuralNetwork` reorders the derivation accordingly (conv filters → LSTM hidden → first-layer
  width → depth). Expected effect on the shipped config: LSTM/HYBRID 16 → 64 units, CONV 16 → 32/64;
  plain MLP unchanged.
- **N1 DONE, with a correction to this report's premise.** Reading the indicator, `EventCode` is
  ±1..7 where the sign is accumulation/distribution and the magnitude is position in the Wyckoff
  schematic (PS→SC→AR→ST→Spring→LPS→SOS) — so it is genuinely *ordinal*, and this report's "event 9
  is three times event 3" framing was wrong (there is no event 9). The real defect is that direction
  and stage are entangled in one scalar across a sign discontinuity — precisely what the base OHLC
  block already fixes by giving direction its own ±1/0 flag. All three signed Wyckoff categoricals
  (`EventCode`, `EventPhase`, `StructuralPhase`) are now split into a direction and a [0,1]-scaled
  magnitude. Information-preserving (the pair reconstructs the original exactly); nothing was dropped
  — including the collinear-but-nonlinear `StructuralPhase`, kept deliberately so this change is
  purely a re-encoding and any effect is attributable to it alone. 13 readings now occupy 16 inputs.

## 6b. POST-DEPLOY ADDENDUM — the first run at B=32 regressed, and why

The change set above was deployed and run on SP500 H1 (four charts, 12:49–13:30). It regressed every
topology. The diagnosis found one root cause that predates F4 entirely, plus two ways F4 made it
visible. Recorded here because the root cause invalidates part of the reasoning above.

### What the run showed

| reading | before (`ee48381`) | after (`0c01dc2`) |
|---|---|---|
| `lstm1` dW/W, eras 2/3/4 | 2.62% / 10.0% / 7.14% | 0.024% / 0.022% / **0.003%** |
| `conv1` dW/W, early → late | 0.52% → 1.18% @ era 42 | 0.35% → **0.000% @ era 30** |
| PAI IS error | 0.41–0.42 @ era 1028+ | 0.48 flat, converged @ era 41 |

`conv1`/`lstm1` in that report read `getWeightsConv`/`getWeightsLSTM` only, so this is unambiguous:
the convolution kernel and the LSTM recurrent block stopped training. The `bn*` figures stayed
healthy, but they are not a counter-example — their norm is dominated by running variance
(`bn2` norm 263,053 against `var` 2.65e+05) and BN running stats update per *sample* in the forward
pass, where batching cannot reach them.

### R1 — THE ADAM SECOND MOMENT WAS NOT ADAM (all four tiers)

Every Adam kernel in the engine stored `v` already square-rooted and then fed that stored value
**back in as if it were the variance**:

```
v_new = sqrt(b2 * v_old + (1 - b2) * g^2)      // v_old is a standard deviation, not a variance
```

That recursion has a fixed point at `v ≈ b2 = 0.999` for *any* gradient below unit scale, because
`(1-b2)·g²` becomes negligible against `b2·v`. The denominator therefore stops tracking the gradient
scale, and `delta = lt·m/v` degrades from scale-invariant Adam into plain SGD with `lr = lt`.

Measured against the shipped `WarriorCPU.dll`
([batch_accum_check.cpp](../DirectML/batch_accum_check.cpp), `TestOptimizerScaleInvariance`),
4000 steps of a constant gradient:

| gradient magnitude | stored `v` | displacement | vs magnitude 1 |
|---|---|---|---|
| 1e+0 | 1.000000 | 1.019 | 1x |
| 1e-2 | 0.999000 | 1.050e-2 | 97x less |
| 1e-5 | 0.999000 | 3.101e-4 | **3285x less** |

A scale-invariant optimizer gives the same displacement in every row. After the fix — square `v`
back before re-entering the recursion, which *is* the textbook second moment, merely carried in
std-dev form so the stored value can be the denominator directly — all six rows read 1.199 and
`v` tracks the gradient magnitude exactly.

**Why this hit the front end specifically.** Conv and LSTM sit *behind* a batch-norm whose running
variance is ~2.6e+05, so their gradients arrive divided by ~500 — deep in the degraded regime — while
the dense stack nearer the loss sees gradients of order 1 and stayed in the working regime. This also
explains a recurring theme in this engine's history: the front-end stage has *always* been the one
that "won't train".

**It was already known, in one place.** `NeuronBatchNorm.mqh` squares the stored value back for
gamma/beta and its comment named the kernels as wrong, but deliberately left them alone because
fixing them "would alter the behaviour of every existing model on all four backends at once". That
is exactly why gamma/beta kept learning while the stages behind them froze. Now reconciled: OpenCL
(`Network.cl` x3), `WarriorCPU.cpp` x3, `WarriorDML.cpp` HLSL x3, the host-side batched step in
`NeuronOCLBase.mqh`, and the legacy scalar tier in `NeuronCPU.mqh`.

The persisted `.nnw` needs no migration — `v` keeps its std-dev meaning, only the recursion changed.

### R2 — mini-batching was never paid for

Two compounding errors in F4, both mine:

- **No learning-rate compensation.** B=32 takes 32x fewer optimizer steps per era. The linear rule
  (Goyal et al. 2017) is for SGD; for adaptive methods the rule is `sqrt(B)` (Krizhevsky 2014;
  derived for Adam in Granziol et al. 2022). Now applied once, in `InitialEtaForOptimizer()`.
- **Patience denominated in eras.** An era is a data pass, so raising B silently made the plateau
  ladder 32x more impatient in the only unit it measures. PAI declared convergence at era 41 on ~49k
  updates where the same config had been finding new bests at era 1028. `TrainPlateauPatienceEras()`
  now stretches it by the same `sqrt(B)`.

Both are exact identities at B=1. `TRAIN_BATCH_SIZE` is 32 → **8**: after the `sqrt(B)` LR bump an era
still makes `sqrt(B)` less progress, so patience must stretch by `sqrt(B)` too — at 32 that is 8 → 45
eras per ladder stage on a topology already taking 70 s/era, at 8 it is 8 → 23. Noise still falls as
`1/sqrt(B)`, so 8 keeps ~2.8x of the variance reduction that was the point.

Note R2 could not have been fixed in terms of B alone while R1 stood: under the degraded optimizer,
averaging B samples shrank the front end's gradient by a further `sqrt(B)` *on top of* the B fewer
steps, and step size was proportional to gradient magnitude.

### R3 — the deployability floor let a one-sided model ship

PAI reported `Sell:0%` recall in all 41 eras, cleared the floor on Buy alone (36.6% against 34%
chance) and deployed — the "buy sprayer" on the chart. `tradeableOK` tested coverage and precision
only; coverage counts directional calls without caring that they are all the same direction. Added
`DEPLOY_MIN_SIDE_RECALL_PCT` (10%), folded into `tradeableOK` so a one-sided era cannot become the
best-so-far in the first place, not merely be refused at the deploy gate. Deliberately far below the
40%-per-class diagnostic, which is unreachable on this data and would block every deployment.

CONV, for contrast, was correctly blocked by the existing floor — the gate works, it was just blind
to one-sidedness.

### R4 — the two chart-cleanup bugs

- **CONV stranded its arrows** because `OnDeinit` was force-terminated: 13:29:58.202 → "Abnormal
  termination" 13:30:03.002, 4.8 s against ~1.1 s for the three charts that finished, having reached
  none of its cleanup. That is MetaTrader's OnDeinit budget expiring, not a fault. `ExtPanel.Destroy()`
  — an unbounded CAppDialog teardown — sat *ahead* of the arrow purge, the same ordering inversion the
  rule there exists to prevent. Arrow cleanup now runs first, and each step is timed so the log names
  the slow one.
- **`persisted 10 ... cleared 0`** on LSTM and PAI is unresolved and needs a run to settle: two scans
  microseconds apart disagreed about the same chart, and the WARNING branch built to catch exactly
  that stayed silent because its rescan filtered on `OBJ_ARROW` in the same way the bulk delete did.
  The rescan now walks every object type, and the both-zero case reports the object counts explicitly
  instead of passing silently.

### Revised deploy notes

### Deploy notes for this change set

1. **Both DLLs must be redeployed** with the `.ex5` — they carry new exports, and now also the
   corrected Adam kernels (R1). Verified: both build variants compile 0 errors / 0 warnings. `build_cpu.bat` and
   `build.bat` copy them into every discovered MetaTrader `MQL5\Libraries`.
2. **N1 forces a retrain** of every Wyckoff-enabled config: the fingerprint gains `|WES:2|` and
   `m_neuronsCount` goes 64 → 67. That is intended — it is also what lets F6's new shape take effect,
   since derived widths are adopted from a model's existing `.cfg` rather than re-derived. A config
   with the Wyckoff events *off* keeps its fingerprint and its model, and will only pick up F6 after a
   manual reset-weights.
3. **First run to watch, in this order**: the startup `config -` line (first dense layer should no
   longer read 16 on CONV/LSTM/HYBRID); then per-era `dW/W` (every stage must move — a stage stuck at
   ~0.000% means the batched path is starving it); then whether IS error falls more smoothly than
   before, which is the whole point of F4.
4. If anything looks wrong, `TRAIN_BATCH_SIZE 1` in `ExpertSignalAIBase.mqh` restores the exact
   pre-F4 update path without touching anything else — including the `sqrt(B)` LR scale and the
   patience stretch, both of which are identities at 1. It does NOT revert R1; the Adam fix is
   independent of batching and should stay on either way.
5. **R1 changes training dynamics for every topology, not just the front end.** The single reading
   that confirms it worked is `conv1`/`lstm1` dW/W staying alive (order 0.1–1%) instead of decaying
   toward 0.000% — check that before any accuracy number.

A further literature-backed option once the above land: deploy the **shadow EMA** net (already
maintained at tau 0.01/era, [Training.mqh:1161-1163](../Expert/AIBase/Training.mqh#L1161-L1163))
as the inference model rather than the raw best checkpoint — that is stochastic weight averaging
in all but name, and it is the standard cure for "the deployed snapshot happened to be a lucky
era". The infrastructure exists; only the deploy wiring would change.

## 7. Expectation setting — what "linear progression" can mean here

Monotone *IS* improvement is achievable (and the fixes above get you close to it). Monotone *OOS*
improvement up to a stable maximum is achievable only up to the information ceiling of the
feature/label pair, and the repo's own instruments — the family-wise selection gate
([Training.mqh:60-78](../Expert/AIBase/Training.mqh#L60-L78)), the MI noise-floor and lag-profile
verdicts — currently place that ceiling at "no deployable directional edge". The correct reading
of a post-fix run: if training becomes smooth, plateaus cleanly, and the gate still says
p_family ≈ 1, then the plateau is *real* and the next lever is the data (features/labels), not
the optimizer. The one measured positive remains excursion *size* (range 4x its null, p=0.005) —
a volatility/risk head, not a direction head. Chasing direction with a better optimizer cannot
overturn a measurement about the data.