I agree with Meela that experts are usually perfectly fine, & even when they're not I can still learn something from them. The only thing that annoys me a bit is when someone goes into a short summary of the life of a character just to answer a question that would've taken one sentence to say. Or, worse yet, all they ever wanted to do was agree but decided to expound upon every tidbit of the character's character. It comes across as: I'm throwing a bunch of facts out here (99% of them everyone already knew) to show that I know quite a bit about this character; though I'm sure they don't mean to come across that way. It mostly happens with newbies, they think that most of the people here know little about Tolkien so they decide to start of with a good post full of education for those that know
far less than them
( I'll admit my first few posts on this site followed that line
).
Cheers,
Estel