r/OpenAI: GPT-5.5 Thinking Noticeably Weaker Than GPT-5.2 at Scientific Reasoning and Staying on Topic — Community Documents Regression

A developer on r/OpenAI reports that GPT-5.5 Thinking consistently underperforms GPT-5.2 on scientific reasoning, argument analysis, and research-oriented tasks — frequently drifting off the actual question posed and losing rigor in critical-sparring sessions. The post is drawing broad engagement as other users share similar regressions in analytical and discipline-focused workflows; separate community reports describe a silent model downgrade pushing Plus-tier users to lighter variants after hitting usage thresholds. No official OpenAI response has addressed a scientific reasoning regression specifically.