No, the comment is right. The prompt had GPT-5.6 reviewing the proof, and the result, unsurprisingly, survives review by GPT-5.6.
Given a new context, why couldn't the same model have a decent shot at reviewing some results? It's not like they identify whether this output is from them and then go "yeah correct", that's not how they work.
Given a new context, why couldn't the same model have a decent shot at reviewing some results? It's not like they identify whether this output is from them and then go "yeah correct", that's not how they work.