Round 2 verification audit for C051

Model: gpt-5

Claim: The steady-state error coefficients shown in Fig. 3a are obtained by fitting the numerical results for p<0.01 and rounding to the nearest integer.

Source alignment: source/supp_content.tex:68-68 (Supp. Mat. S2)

Prior official verdict: verified with failure_reason None.

Executable evidence: run.py. Sandbox rerun logs: run.log.

Independent audit: I scanned the copied script for imports/shared helper dependencies and reran it through the sandbox. The code is self-contained in this attempt directory and targets the claim strategy: Reproduce the per-channel linear fits for p<0.01 and confirm the rounded integer slopes reported in Fig. 3a.. I checked the relevant family model rather than relying only on exit status; the rerun is treated as one reproducibility input.

Decision: Round 2 verdict is verified with failure_reason None and limitations []. Notes: Per-channel steady-state error slopes for all 16 M_{i,j} (optimal params, error after A, 6000-cycle power iteration, p<0.01, rounded to nearest integer): all 9 GLOBAL channels -> 0 (max |slope|<1e-6, matches 'fidelity independent of global errors'); 6 LOCAL channels nonzero: bit/Y locals (I_eX_e, X_eI_e, I_eY_e, Y_eI_e) -> 5 (5.04), phase locals (I_eZ_e, Z_eI_e) -> 4 (3.99). Reproduces the Fig 3a structure (global->0, local->nonzero integers); local bit-flip ~5 consistent with main-text 5.2p (C025). Verified by close match.