Omg, use common sense mate. If a rogue comes against you, he'll probably only damage one char at the time, so you will need a macro to heal 1 person. Let's say a mage step in and freeze you all with frost nova and start spamming you with blizzard, then a macro which heal everyone would be of great advice here. You'll have to be creative since no situation in PVP is ever the same twice.

And no, there's is no "ultimate macro" to heal you.