Ratification: ADR-0250 Status Proposed->Accepted; §10 ruling record stamped
(Shay, citing the acceptance-evidence pack as-is; full-holdout 50/50 wrong=0
affirmed; next arc = seal dev-holdout-2, dev-1 pinned as regression floor).
Review findings (Shay, PR #74, non-blocking):
1. Instrument module docstring updated from 'Three deterministic domains' +
'GSM8K NOT ingestible / no compiler' to the four-domain post-0250 reality
(arithmetic-chain solves the full dev holdout; frontier surfaced in scope).
2. Restored per-case refusal reasons: _corridor_and_baseline now raises
MultiRegisterError (not bare None); the domain loop records refusal.reason
and distinguishes graph_parse_failed. 'Recorded, never silently dropped'
stays literal (0 rows at refused=0, but the path is honest).
3. Tightened the Tier-1 try to wrap compile_turn_program only (execute outside),
so a future typed execute raise surfaces as a Tier-1 failure instead of
silently rerouting into Tier-2 and masking a regression; added the note that
Tier-2 fails closed on non-convergence while Tier-1 records-only, gold
comparison binding wrong=0 on both.
10/10 instrument pins green.
[Verification]: uv run python -m pytest tests/test_adr_0249_arithmetic_lift.py tests/test_generalized_lift_instrument.py -q
Instrument: the arithmetic-chain domain now routes each real GSM8K dev case to
Tier-1 (single-accumulator) or Tier-2 (multi-register / summation) and compares
the corridor to a symbolic fold of the SAME compiled program. Recorded coverage
moves 26/50 -> 50/50, 0 refused, PARITY (wrong=0) — the measurement catching up
to the capability. Scope note corrected (full holdout closed; remaining frontier
= derived-operand transfers + non-affine kinds + >5-atom deduction, all 0 on this
holdout). Updated the ADR-0249 instrument test pins (26->50, refused 24->0).
ADR-0250 (Status Proposed, no self-Accept; §10 ruling awaits Shay) + acceptance
evidence: multi-register model, relative conservation, atomicity, certified
summation, chain-of-custody, and the full-holdout 50/50 wrong=0 result.
10/10 instrument pins green.
[Verification]: uv run python -m pytest tests/test_adr_0249_arithmetic_lift.py tests/test_generalized_lift_instrument.py -q
