> if you recently learned/mastered a topic, you're in a far better position to teach that topic than an expert

That can work, assuming that (1) the particular difficulties you encountered will generalize to most other learners and that (2) being good at programming equates to being good at pedagogy.

>I recently read a comment (I think it might have been on HN, but I can't find it)

I think it probably was on HN.