I don't really mind the derails, unless they are mean or someone comes in and just vomits their own unrelated issues on a positive thread which then makes it uncomfortable for anyone else to post.
Oh yeah, andddddd I especially hate it when someone comes in and starts correcting grammar and spelling and they say stuff like they can't concentrate because someone spelled "a lot" "alot". It makes me wonder if maybe being a good speller is all they have going on in their lives.
Something recently I have noticed is people questioning or ridiculing original posters for starting treads at all. Maybe it has always gone on? If someone starts a thread, then they probably are looking for some sort of answer.
Some of the funniest threads ever have been derails.
I love you guys man!