@@ -85,7 +85,9 @@ All rows passed the CER parity gate at release. Readings:
   coverage (the subset lesson from run-002). Reported exactly as
   measured — no threshold-moving.
 - Engagement was verified independent of outcome: gates moved off zero
-  by step-500 (0.0008-0.0028), CE 2.07 → 0.02 over 10,995 steps.
+  by step-500 (0.0008-0.0028) and settled at 0.034-0.053 by step-10,500
+  (15-20x) — the memory branch contributed measurably but modestly,
+  matching the 0.70pp outcome. CE 2.07 → 0.02 over 10,995 steps.
 - Launched 2026-08-27, A10G, labels reused from run-002 (single-variable
   design). Survived one mid-run eviction: resumed from step-2000.
 - **Hypothesis:** the 5.68pp teacher→student gap (r6 2.5815 → ByT5-small
 
@@ -222,6 +222,25 @@ mojibake labels (byt5 decode_joined bug), the second silently resumed
 from the poisoned lineage's checkpoints (now guarded by labels.sha
 digest matching), this one clean end-to-end. CE plateaued at ~0.016.
 
+### run-003-pkm — memory-layer student (2026-08-28, research run)
+
+The qwen-next capacity experiment (EXPERIMENTS.md E2): identical to
+run-002 except three product-key memory layers (+85.9M lookup params,
+zero-init gates) on the ByT5-small decoder — single-variable.
+
+| Model | DER-CE (full 1,200) |
+|---|---|
+| Teacher (r6, full-set) | 2.5815% |
+| **Student + PKM memory (run-003-pkm)** | **7.5553%** |
+| Student vanilla (run-002) | 8.2590% |
+
+0.704pp of the 5.677pp teacher-student gap closed (12.4% relative) at
+near-zero added compute — below the pre-registered ≥1.0pp win bar, so
+the memory axis is real but not the dominant term of the gap. Gates
+verified engaged (0.034-0.053 at completion). Not shipped; the vanilla
+client rung stands. The optimizer A/B on the same architecture
+(run-004-pkm-muon) is recorded in EXPERIMENTS.md E3.
+
 Leaderboard context (SadeedDiac-25, Misraj evaluator, zero-skip,
 harakat-projected DER-CE): the teacher tier (r6, 580M) at 2.5793
 (reproduced at 2.5815, 2026-08-26) is the best dedicated model measured