Did you know not performing as you think another player should in a group

[xJimmehx]

deliberately delaying their progress through an inability to perform

Deliberately means they did it on purpose.
Inability means they can't do it even if they wanted to as they dont know how.

If you want to play the game your way, and expect/force everyone to accept and validate your playstyle and not hold you to any other standard but your own, then playing a multiplayer game isn't for you.

Tell that to the people kicking everyone that plays in anything but their preferred way.

Personally. I think everyones wrong. Both sides of the community act like they expect something from the other. Be it accepting ones playstyle/dps or demanding other to change to suit your taste.
If i told an unknown man in a store this evening "hey your shirts offensive because it has nudity. You need to change it." He'd probably tell me to F$%k off or look at me like I'm stupid because i have no control over him or his wardrobe.
People think sharing an instance is reason enough to be owed something.