How much of an imbalance would it create if...

... Tanks and Healers were combined into a single class with 99% of the skills of both classes? Crazy? Stupid? Maybe. But let's try it for a month and see. At least this way we'll never have to worry about someone shouting al day, "K95 LF Healer!!!!!!! (exasperated) !!!!!!!" :)

How much of an imbalance would it create if...