I don't know why you guys actually do less when playing multiple classes than you would for just one. I don't feel good about the thought of using the ability to multibox to essentially reduce each character to a few skills on one button without the ability to devise a case-specific plan. It just seems to go against the point of having a multi-class setup.
I agree. Having said that my team is still succeeding quite well with basically a set of healer macros and one, all purpose DPS button, and a few tank macro's.

Reason? My team is 60 atm with a 70 lock demonology specced. Most of my fights, even "boss" encounters have been made trivial by the lock and his pet. I'll have to "learn up" to what you describe pretty soon as I start hitting Outland instances. Looking forward to it. It is a bummer right now realize I'm barely using the abilities of my disparate classes.