[CogitoCogito]

> He had the most extensive mental catalog of the wrong ways people could understand and the failure modes of students.

Back when I used to teach math classes as a grad student, I realized that a teacher has to actively work to keep that "mental catalog" for students. The problem is that longer you are in the math world, the clearer the subject becomes. The result is that to you the teacher it really just becomes braindead obvious what's going on. As time goes on, you have to fight this "problem" more and more to keep touch with the issues your students are having.

[seanw444]

I think that applies to many topics. Maybe math more than others due to the complexity of it all, but it seems commonplace that as you become more of an expert on a topic, the more detached from "newbyism" you become. It's harder to put yourself in the shoes of a beginner to see what they're seeing and know what they're missing.