Abstract
Following arXiv:2607.25507, this report examines whether phase-derived features improve endpoint prediction over a combined baseline in two settings: a sealed contradiction comparison and a retrospective analysis of answer changes across matched pressure prompts. Study 1 froze a contradiction-category pipeline before sealed scoring. On 1,136 eligible primary cases, adding PC-2 produced a paired AUROC difference of +0.00087. The 99% bias-corrected accelerated interval included zero, and the prespecified +0.05 threshold was not met. A replication role with 1,063 cases showed a same-direction increment of +0.00019. The replication-direction condition passed, but both primary conditions failed, so advancement failed. Study 2 developed fifteen treatments on blocks b0-b4 using 1,415 eligible answer-change comparisons and twenty-repeat, five-fold grouped cross-validation. An execution on 9 September 2026 recomputed development statistics from saved prediction units and applied a three-condition gate; no treatment advanced. Layer 25 had the only positive mean-repeat PC-2 increment, approximately +0.00027, with a favorable sign in three of five seed blocks. These statistics measure development consistency, not whole-seed-block holdout performance. Agreement with earlier selection records does not establish an earlier notebook execution or that the rule was fixed before inspecting development results. The planned b5 selection and b6 evaluation were not completed through this gate. Neither study demonstrated the incremental benefit required by its applied advancement rule. The findings limit support for the evaluated feature constructions; they do not test the rotary score identity, its local pre-softmax bound, or the effectiveness of execution-boundary governance.
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