"Sees dungeon party with two empty slots near last boss, joins with friend, kicks other two and brings in two more friends."

Not that stuff like that would be frequent, (I would hope, but it wouldn't surprise me.) But it would be detrimental.

This is why I am in favor of the current system. Its blind and mkes doing stuff like the above very difficult. Also, Aurum Vale! Pass!

I think its a great idea in its pure form, but you do have to take the snakes and trolls into account when incorperating something into a game.