Quote Originally Posted by Hanabira View Post
I love how people are saying that its intended that "join in progress" should ONLY allow you to join dungeons in progress. But here is a good question, if everyone could join an in-progress dungeon and not also be in the queue to start from the beginning, then who is going to start fresh dungeons?
This. That's the reason why the feature lets you to ALSO join parties in progress (and not only). So basically if a tank is withrawing because he doesn't join in-progress run, he does NOT use the feature as intended.

Is he allowed to do that? I guess yes, it's not against the rules and SE can't really verify the reason of the player withrawing.
Is it ethic? IMO not.