Didn't Age Of Conan have a similar concept? I don't see any valid reasoning as to why someone will offer an option like this, too many varibles come into play some maybe undetected before it's too late, and fixes may or may not happen in time, possi…
How about contested zones? What prevents a 1v1 turning into a 2v1 with your own faction member helping the other faction? Maybe AOE heals can affect opposing by healing them as well....