second review round: tempered claims, robust statistics, corrected technical statements

Analyses (figures/stats_llm_epistasis.py, committed + reproducible):
condition-clustered bootstrap CIs (functional measures exclude zero:
dis_raw [+0.04,+0.69], conf-weighted [+0.02,+0.68]; gradient alignment
[-0.59,-0.06]; geometry straddles zero), PAIRED predictor contrasts (not
individually significant — stated), leave-one-condition-out held-out
prediction (functional replicates, geometry ~0, performance baseline
unstable), three outcome references (ordering sensitive to reference —
reported, with the mechanism), between/within-axis decomposition
(within-conflict identification impossible by design; the compat axis
identifies), and seed-level paired reliability (routing/directed beat
soup 3/3 seeds incl. one catastrophic soup failure; CI-width fragility
claim withdrawn).

Renames and corrections: "decisive experiment" -> "controlled predictive
test"; "operational epistasis" -> "confidence-weighted functional
conflict (proposed proxy)"; "functional by construction" -> "controls a
major source of coordinate mismatch / conflict-associated" (module,
configs, READMEs, figures); SI proposition's "chord" defined precisely
(endpoint-loss interpolation, invariant) vs the path (not invariant) +
no-global-optimality caveat (removable = lower bound, residual = upper);
snowball count != performance cliff distinction added; claims table
gains four rows (grid finding / weighting NOT supported / functional-vs-
all-geometry not established / operator choice open); §1 ladder states
the prediction rung as a bounded small-model result.

paper/response-to-review-2.md: point-by-point, opening with the
bookkeeping correction (E13b/c were in the reviewed draft — revised
interpretation, not new results). READMEs rewritten around the four
analyses with the chronology (prospective/adaptive/post-hoc) disclosed.
151 tests green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BkRLcc18rwT2Lysu6PbG7v

results/llm_merge_seeds/README.md

@@ -18,18 +18,22 @@ the single-seed run — decisive at 7B) and the **worst-family signature is unam
 vs ≤0.16 for any parent — only recombined models are competent everywhere.
 
 ### (B) Union vs fusion, hard benchmark, 3 seeds (`llm_moe_hard_seeds/`)
-Routing (union) 0.274 ± 0.026 overall / 0.238 ± 0.024 worst-family; fusion soup 0.174 ± 0.102 / 0.088
-± 0.093; ties similar; best specialist 0.199 ± 0.026. Union beats fusion on both metrics — **and a new
-finding: fusion is seed-FRAGILE on hard tasks (CI ±0.10) while routing is seed-stable (±0.026).**
-Averaging's outcome depends on which specialist minima the seeds happened to find; selection-based
-recombination is reliable. (Learned router still = oracle: lexically distinct families, known rider.)
+Routing (union) beats fusion **in every seed** (3/3 paired, both metrics; e.g. overall per seed:
+routing 0.258/0.300/0.262 vs soup 0.212/0.238/0.071). The paired per-seed values also show *why*:
+seed 3's soup failed catastrophically (0.071 overall, 0.000 worst-family) while routing was unaffected
+(0.262/0.225). Seed-level sd: soup 0.090 vs routing 0.023 — suggestive of a genuine variance
+difference, but with 3 seeds this is an observation, not an estimate; the robust statement is the
+3/3 paired ordering plus the observed catastrophic-failure mode that routing is structurally immune
+to. (Learned router still = oracle: lexically distinct families, known rider.)
 
 ### (C) Directed offspring selection, hard, 3 seeds (`llm_directed_hard_seeds/`)
-directed_overall 0.221 ± 0.026 (> soup 0.174 ± 0.102 and > best specialist); directed_balanced
-worst-family 0.158 ± 0.036 (> soup 0.088 ± 0.093). Directed selection both beats and **stabilises**
-the a-priori soup; per-input routing (B) remains above any single global blend, as before.
+directed_overall beats the a-priori soup **in every seed** (3/3 paired; 0.225/0.242/0.196 vs
+0.212/0.238/0.071 — including rescuing soup's catastrophic seed); directed_balanced worst-family
+0.158 vs soup 0.088. Directed selection both beats and stabilises the blend (same 3-seed caveat as
+panel B); per-input routing remains above any single global blend, as before.
 
-**Read together:** all three recombination claims hold under seed replication, and the operator
-ordering (route > directed-select > soup, on headroom tasks) is not only a mean effect but a
-*variance* effect — the union/selection operators are the reliable ones. Base: Qwen2.5-0.5B-Instruct;
+**Read together:** all three recombination claims hold under seed replication with consistent paired
+ordering (route > directed-select > soup in every seed on headroom tasks), and the per-seed values
+surface a failure mode — occasional catastrophic soup merges — that the union/selection operators
+avoided in every observed case. Variance *estimates* await more seeds. Base: Qwen2.5-0.5B-Instruct;
 statistical (per-seed) reproducibility per blueprint §4.