Back in AW there was friendly fire. If you killed two friendlies you got PNG'd for a while (24 hours IIRC). The fraggers then got more creative, sitting at the end of the runway damaging airplanes before they got off the ground; smoking the engines, shooting off parts, anything to grief players short of killing them. It effectively ended those players sorties before they ever got off the ground and the fraggers were able to totally take a field out of action.
No thanks. I'd be gone the minute that change was enabled. I've already been there.