We asked @max_a_schwarzer (Researcher @OpenAI) about post-training improvements in GPT-5: "The thing that is most impressive about GPT-5 is how much getting all of the details right matters." "The team went off and did a deep dive of completely rebuilding the post-training stack, and it turns out that when you do that, you get results that would have taken another order of magnitude in pre-training improvements to produce."