Good solution, which works for both sides would be to allow everyone to que for the job they want to be, and play in the world with another class and auto switch or force switch once they are in the dungeon. Then people wouldn't care because they wont have to stop what they are currently doing and change classes while a tank is spamming DF. You can not blame tanks for being efficient as possible. Everyone knows FATE grinding is cheese, yet everyone does it. Why, because its most efficient.

Personally i don't care either way. I have always been tank class in MMO's and i am one now. I dont have the join in progress checked anymore because the few i did join were problem groups. I dont mind one player being bad or a group of new, but when you pull that once a week group that cant manage to kill the bees for example, you dont want a higher chance of getting them.

The bright side is when you see that tank cheesing the que, you know that you're in the front of the que