[krageon]

> insisting that somebody is ignorant is pretty rude.

This person claimed ignorance of the other party once and in context it's a very reasonable conclusion. There's nothing rude about that, except maybe when you find the state of ignorance bad in and of itself. That doesn't really make sense, as all humans are born ignorant. That's just how things are and that's what teaching is for. Which is what the post being discussed attempted to do.