@@ -1025,3 +1025,17 @@ much as the knowledge. Paradigm-table aux is closed (no dose tuning,
 no convention-normalization retry recorded as future work; a lexical
 lever, if ever revisited, must be rendered into benchmark-convention
 running text). The frontier mover on record remains the r7 news mix.
+
+## run-020 plane-distill — label-limited distillation loses to raw-text scale (2026-10-05)
+
+Arm B of the plane-large verdict follow-up: ByT5-small plane encoder
+trained on r7 teacher labels (29,322 unique pairs ×6, 3 epochs) scores
+full-set **Total DER 4.4462 / Morph 2.8620**. Two clean readings:
+(a) on MATCHED teacher-label supervision the plane architecture beats
+the seq2seq student (4.4462 vs 4.5701 — architecture advantage
+confirmed independent of supervision); (b) label-limited distillation
+loses to raw-text diversity at scale (run-018's 551k unique units →
+3.5905) — for the plane family the lever is unique-data volume, not
+supervision source. A full-corpus teacher labeling pass (~15-20h GPU)
+is the conditional distill follow-up, only if the epoch-2 arm falls
+short of the 2.2864 gate.