it always happens, where you form a duty finder group after a long wait. then right after that long wait, a tank or healer leaves, or even a dps. now, you wait even longer than before to find the new player, or you disband after fifteen minutes or take that thirty minute penalty as well. it also happens in trials, after 1 wipe, half the group leaves. now the trial is screwed because no one clicks join in progress. this is why i think it should be mandatory to join a group in progress if needed. i actually turned "join in progress off" because oftentimes i will join a group that is missing a tank and will have wasted my time in queue.