Oversight When the Signals Give Out: the Activation Fallback and the Taste Reward

Joint answer to two #oq/now items that are one boundary seen from two sides — what to do when the legible signal (a monitor's readable trace, a trainer's verifiable reward) runs out. (1) The fallback for illegible CoT already exists and is partially deployed: the white-box stack (contrastive probes → NLA verbalizer → J-lens) reads the channel the model isn't optimizing to present, found the ~5% unverbalized grader awareness CoT missed, runs at traffic scale, and ships as default injection probes — but it has its own floor (workspace-independent 'automatic' computation evades both monitors) and an unresolved arms-race question, and Opus 5 shows legibility decay isn't monotonic, so the fallback is a complement, not a successor. (2) Taste entering the RL mix would today mean a reference-free LLM-judge reward — precisely the regime where judges over-credit (up to 85% verdict flips when a reference is added), kappa deflation hides unreliability, and models already model graders internally; prediction: proxy-smoothing into a confident house style rather than genuine taste peaks. The binding constraint is evaluator independence and reference-grounding, not verifiability-in-principle. **Postscript 2026-08-04: the answer-2 prediction was independently corroborated** by Zhou (arXiv 2607.05904) — self-play against a reference-free judge drives its pass rate 0.716→0.938 at flat 0.209→0.202 true accuracy, with an oracle-reward control attributing it to the judge; the fix is the judge committing its own answer before conditioning on the candidate (0.719→0.012). Two revisions: the attractor is plausibility, not house style (hacked outputs are *shorter*), and the council-of-judges objection was right on lineage-independent grounds too — cross-family ensembles share the basin