Operator ruled the probe port for validation; runbook updated to match.
The bf16 MTP acceptance gate is ~56 GB resident, which on a full 97.9 GB card
means downing meromero-charrp as well as gen -- freeing gen's 0.43 (~42 GB)
alone is not enough. Two seats down to answer one question.
compare_mtp_head.py answers the common case for free. The
Qwen3_5ForConditionalGeneration wrapper never loads the MTP head, so PEFT
merges, Heretic runs, and llm-compressor passes all leave mtp.* as it came
from the base. It hashes a candidate's 15 mtp.* tensors against the
incumbent's grafted-verbatim head -- the one measured at 47.7% acceptance in
production through this exact pipeline. Identical means the acceptance
question is already answered; different means the head was edited and the
real gate is warranted; missing means it was dropped.
CPU only, reads just the shard holding mtp.*. The runbook states the residual
risk plainly: an identical head proves the head is intact, not that the
abliterated body still drafts well with it -- which the Stage-3 acceptance
measurement on the 22 GB quantized build catches anyway.
Candidate MuXodious/Qwen3.8-27B-absolute-heresy (Heretic v1.4.0 + SOMPOA,
trial T377), pinned c2374593. Beats the incumbent on both axes: refusals
2/101 vs 12/100, first-token KL 0.0759 vs 0.1191. Structurally a clean full
checkpoint (1199 tensors, 15 mtp.*, 333 visual.*, lm_head), so the existing
mixed NVFP4+FP8 recipe applies with no graft-and-reconstruct.
Runbook carries the bf16 MTP-acceptance gate before any quant spend, the
llm-compressor ignore-pruning foot-gun, the three measurement traps
(cache-busting, unseeded prefill nonce, PPL with spec off), the .env 0600
sudo trap, the GPU0 co-tenant starvation risk, and rollback.
Flags that the candidate is a 2-day-old RC1 whose own card carries a broken
GGUF benchmark block (RC1 and RC2 report identical at-chance scores across
three benchmarks), so its numbers are claims rather than measurements.
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