# `[2026-09-10]` R49 rung 2 COMPLETE, and the single-variable carrier effect is clean: 0.6B held-out 3.329 vs 1.7B 3.018, Δ0.31

**R49 rung 2 COMPLETE, and the single-variable carrier effect is clean: 0.6B held-out 3.329 vs 1.7B 3.018, Δ0.311 nats.** Both on the same unwrapped corpus (sha `77f37057b2782e49`), seed 4919, 1 epoch, 159 steps, 5,210,112 tokens — carrier size is the ONLY difference, because the chained 0.6B rerun closed the confound the unwrap opened. ⚠⚠ **DO NOT compare either against the original wrapped-corpus 0.6B run's 3.172 — that comparison is INVALID and reads backwards.** Different corpus means a different held-out set: the wrapped version's 5.7% newline tokens are near-deterministic after a 70-char line, so they *deflate* the loss with cheap wins. Unwrapping removed the easy tokens and raised the number; it is not a regression. ⚠ **Correction to my own earlier claim**: I twice described the 0.6B as "still descending, undertrained" at 3.172 — the series (3.176, 3.173, 3.172, 3.172) shows it FLATTENED. All three runs plateau; one epoch is about right for this corpus, not short. **Three-way eyeball booth** at `http://10.100.10.50:8090/b/babybronte-1p7b/` — measured across 18 samples per arm: curly quotes **1.7B base 0/18 → 1.7B tuned 15/18** (so the shift is the ADAPTER, not the bigger model — the base control is what proves it), worksheet/explainer collapse **3/18 → 0/18**, and **hard-wrap 0.85 → 0.18**, confirming the corpus unwrap carried through into the adapter. **Sense partially returned**: 1.7B produces locally coherent sequential Victorian prose where 0.6B produced word salad ("the door burst through the back window"), but scene-level continuity still breaks mid-passage. ⚠ Curly quotes are slightly LOWER at 1.7B (15/18) than 0.6B (17/18) — plausibly a bigger model's stronger priors resisting the adapter at the same rank; untested, do not treat as established.