I rarely post but couldn't resist such a great topic. I play all three roles and run in regular ops groups. I know how to play each role properly and really enjoy doing all three. I have developed a few habits along the way dealing with this very issue. I always give the offender (s) a friendly warning and some guidance if they just don't know how to play their spec. After I've done so.... When I'm tanking, if I get a jumpy dps that keeps leaping to elites before I get there, I just simply refuse to taunt, if they want it so bad....they can have it. I generally warn the healer when I do though Sometimes as a preventative measure (especially when I'm on the shadow) I just blaze ahead and stay a few seconds in front (with my eye on heals' resources) When I'm healing (after warning tank) I just simply let them die if they jump ahead of the tank. After a few times of that they usually get it. I refuse to burn up all my force trying to keep a foolish dps alive...properly geared tanks are much easier to heal. My main is a dps shadow and I pay extra attention to my interrupts and focus target, if I see I'm the life of the party, I use my agro drop and try to keep threat low for a bit. It's one thing to not know MMO roles (I came from a FPS background...this is my first MMO), but it's another to just disregard them.

I beat subject Alpha on Taris by myself at level 50. He drowned my companion though