It seems plausible to me that GPT-5-Thinking is an enhanced version of o3, rather than a completely different model with a separate post-training process. There’s an example in METR’s report where GPT-5 uses the words ‘illusions’ and ‘overshadow’ as well, which strengthens the case for this. Are there strong reasons to think that o3 and GPT-5-Thinking were post-trained completely separately?
It seems plausible to me that GPT-5-Thinking is an enhanced version of o3, rather than a completely different model with a separate post-training process. There’s an example in METR’s report where GPT-5 uses the words ‘illusions’ and ‘overshadow’ as well, which strengthens the case for this. Are there strong reasons to think that o3 and GPT-5-Thinking were post-trained completely separately?
That seems possible, but GPT-5-Thinking is a better model in many domains, so I’m guessing there was quite a bit of additional training involved.