My druid tank in TBC, I would always mark targets each pull. My num pad is bound to each marker so I can quickly mark targets. I would also say to them to follow kill order and 95% of the time it would be a smooth run. If they manage to pull aggro, I will try my best to get them back on me(usually a taunt + maul) but if they keep topping me, well... I let them die.
Usually after a few deaths, they either cuss me out and leave(ohhh k) or they learn to stop doing that cause I'll let them die.