Their neutral harness is not very good though, if I read it right, it doesn't preserve the reasoning state between turns. No real harness discards reasoning state like that.

Yeah that must be it. OpenAI doesn't want to disclose internal reasoning, that's why thats typically encrypted_content in OpenAI codex session ledgers etc.; leveraging responses API preserves reasoning server side all the way till a final answer is made; so that's very impressive and to me the score that matters.

Yet it is an impressive number. But yeah when you see a number 99 you have doubts. Thanks for the link

Interesting both this and Sol got approximately a 37% boost with the custom harness.