I knew of LW’s existence before HPMoR, through the same source that referred me to HPMoR (ESR).
I registered mostly to comment on this post.
I’ve been reading the Sequences.
More stuff about Bayes’ Theorem (my extent of knowledge before I read the Intuitive Explanation was the idea that there will be many false positives on searching for rare events).
No.
There’s mention in the fifth book of canon that Neville gets a fat lip and is unable to pronounce spells in battle (he ends up just stabbing someone with his wand).