Thanks for the replies. This has given me a lot to think about.

@Ellay : would this not cause interference with either of your rotations? Let's pick druid for example, if your dps rotation is doing solar wrath and you click to start healing but he still spams the dps keys, you have no control on whether his next spell is a heal or a dps spell? Don't you run into problems where you need a heal but it just never happens?

As to Zok's comment, you are really making me rethink the whole druid healer thing. Reason I chose him was because it is my main character and has the highest ilvl but I may need to rethink this in favor of a other class untill I can fine tune my entire setup.