Has it always been on? It's basically impossible to not kill team mates a few times, and I just lost a pretty good game because one of my team mates killed me when I was the last defender back and he sent the ball carrier the rest of the way to the goal.
Kind of a lame way for things to end.
No other wise it would be easier to take advantage of it ie boosting teammates
Can't turn friendly fire off cuz then the bad players start launching their runners like in halo 3. And as funny as that was when they couldn't figure out how I would stop it every time, it wouldn't be good. Just watch your radar and stay spread out. If you have to attack with teammates around, use sword or a melee attack.