And yes, the Aumann agreement theorem does not say what nearly everyone (including Eliezer) seems to intuitively think it says.

Wonder if a list of such things can be constructed. Algorithmic information theory is an example where Eliezer drew the wrong implications from the math and unfortunately much of LessWrong inherited that. Group selection (multi-level selection) might be another example, but less clear cut, as that requires computational modeling and not just interpretation of mathematics. I'm sure there are more and better examples.