How Corrupted Chain-of-Thought Exemplar Answers Shift Internal Answer Preferences

A correct generated answer does not reveal whether a model ignored an incorrect exemplar answer or recovered from its influence. This raises three questions: (i) does reasoning remove the internal effect of an incorrect exemplar answer, (ii) which components carry that effect, and (iii) does that effect track final-answer accuracy? We study multi-hop comparison questions from 2WikiMultiHopQA, replacing only each retrieved exemplar's answer line with either a plausible but incorrect competing answer from its own source question or an unrelated same-category answer, and adding a reasoning–answer factorial that separates the answer-line effect from exemplar reasoning that contradicts it. We measure the target question's gold-versus-foil logit margin before and after reasoning in Llama-3.1-8B-Instruct, with a same-item cue-probe replication in Qwen2.5-7B-Instruct. Reasoning–answer inconsistency is the largest resolved effect in both models, though weaker in Qwen, and in Llama reasoning preserves it mainly through trace-following. Causal interventions identify five layer-15 writer heads and distributed upper-layer attention as shared endpoints for inconsistency and the smaller answer-plausibility effect; a low-dimensional writer signal reaches the layer-16 MLP, and query direction mediates part of the aligned answer-plausibility effect. Neither the corruption-induced margin drop nor its trace-following component detectably predicts factorial generation failure, and two manipulations differing fourfold in margin effect produce similar accuracy reductions. These results separate internal answer competition from successful output recovery.