I don't really understand the way they queue people for raids and dungeons. It seems to me that when you have someone not accept that the queue system reshuffles you back into the system with an entirely new set of people as opposed to keeping the current group together and simply adding whatever role failed to accept. At least that is what my experience seems to show.

Very frustrating when 23 people are there and one doesn't accept and you then find yourself in a queue with less than half that number.