Manuscript revision and pending experiment work, snapshot before restructuring

Clarity pass over the main text (36-item audit), Discussion rewrite and cut,
acknowledgements, Souly et al. as ref 62, lettered SI panels, model section
moved under Results; plus the untracked curriculum/society/compose/smol
configs, runners, figures, stats and tests that the SI already cites.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Y64o8FKP7rCuXzC48pxpMm

configs/llm/compose_s1.yaml

@@ -0,0 +1,55 @@
+# The composition campaign, seed 1 (prereg v3, amended after the generation-0 sweep of 2026-09-07).
+#
+# Arms. The gen-0 sweep found that the merge *weighting* dominates the operator: the a-priori 0.5/0.5
+# blend fails under both operators (surplus -0.020 cat, -0.093 linear) while a selected weight passes
+# (+0.080 linear at 0.2/0.8, +0.027 cat at 0.3/0.7). Weights are therefore chosen each generation on a
+# disjoint validation split (E10, directed recombination) in every arm, and the operator is an
+# explicit per-arm setting:
+#   dry      — linear operator, no grounding      [H2, H3, H5: does composition survive drift?]
+#   grounded — linear operator, g = 0.10          [H4: does immigration arrest it?]
+#   dry_cat  — concatenation operator, no grounding [H6, revised: does the operator ordering hold
+#              across generations, or only at gen 0?]
+experiment: llm_compose
+kind: llm_compose
+base_model: Qwen/Qwen2.5-1.5B
+seed: 1
+generations: 6
+arms:
+- dry
+- grounded
+- dry_cat
+g: 0.1
+n_hard: 150
+n_gsm8k: 150
+n_mbpp: 100
+n_probe: 60
+k_inherit: 300
+epochs: 3
+conf_gate: 0.85
+spec_train: 1200
+spec_epochs: 3
+max_new_tokens: 320
+batch_size: 16
+score_batch_size: 4
+train_batch_size: 2
+train_max_len: 448
+resume: true
+lora:
+  r: 16
+  alpha: 32
+output:
+  dir: results/llm_compose/s1
+arm_ops:
+  dry: linear
+  grounded: linear
+  dry_cat: cat
+n_hard_val: 60
+merge_weights:
+- - 0.5
+  - 0.5
+- - 0.3
+  - 0.7
+- - 0.2
+  - 0.8
+- - 0.1
+  - 0.9