thing is they only get the penalty if they leave first. they will tell you to leave if you don't like how they play. so no, they don't even have to wait 15 min.
granted, if there was no penalty things would be even worse right now, but I still say we shouldn't give these people more power than they deserve. I've been saying for a while now, someone make a wall of shame website. these people should not be given the chance to 'eventually' run the hard content, the stuff that you can't do with a random dutyfinder group.
heck, I'd do it myself if I knew how.
