results: close context-vectorizer C2 recovery

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@@ -326,6 +326,34 @@ normalized local deltas do not remove the basin variability. This points to a re
 limitation of the fixed linear `A_l c` vectorizer: on a compositional target, the correct hidden
 direction depends on neural state as well as the two-dimensional output error.
 
+## C2 bounded context-vectorizer recovery (validation only)
+
+To test the identified representation bottleneck, the apical vectorizer was extended to
+`A_l c + G_l vec(c outer tanh(h_top))`. The gated path is zero-initialized, trained by the same
+local perturbation regression, and vanishes in neutral periods. After a task-seed-0 development
+screen selected `eta_A=0.01`, K1/e4, an independent frozen panel used new task seeds 3--5 and five
+student seeds, again crossing BP, FA, DFA, and SDIL at d1/d4. All 120 runs came from clean revision
+`b18227f`; independent test sets were never evaluated.
+
+| method | depth | validation acc (%) | d1-to-d4 gain | d4 lesion drop |
+|:-------|------:|-------------------:|--------------:|---------------:|
+| BP | 1 | 68.633 ± 5.351 | — | — |
+| BP | 4 | 97.187 ± 1.532 | +28.553 | +34.170 |
+| FA | 1 | 52.640 ± 4.528 | — | — |
+| FA | 4 | 80.763 ± 20.592 | +28.123 | +20.313 |
+| DFA | 1 | 56.313 ± 8.374 | — | — |
+| DFA | 4 | 77.097 ± 17.667 | +20.783 | +25.393 |
+| context-SDIL | 1 | 63.977 ± 8.636 | — | — |
+| context-SDIL | 4 | 79.120 ± 22.765 | +15.143 | +27.150 |
+
+Context conditioning raises SDIL's recovery of BP depth gain from the linear panel's `21.0%` to
+`53.0%`, confirming that state dependence was a real bottleneck. It is still below the frozen
+70% requirement, while FA recovers `98.5%`; context-SDIL's d4 mean is `1.643` points below FA.
+Exactly 10/15 SDIL pairs gain with depth and 10/15 are hurt by the lesion, but one d4 run ends with
+nonfinite loss and chance accuracy. **The independent recovery gate fails and C2 test remains
+prohibited.** A richer vectorizer can improve mean credit without curing coupled A/W basin
+instability; this is now a documented limitation rather than an oral-level scaling result.
+
 ## Paper-faithful non-backprop baselines
 
 `PETITE` in the initial request is treated as **PEPITA**. Implementations and hyperparameters were