+ surrendering imo has to be done in a surprise fashion. not face up yelling at each other.
If you are in each others face exchanging paint, and no one backs off or calls them selves out, well you know it will hurt because by now you are pretty close. You didn't back out, you didn't call your self out. It was your decision, you knew what you were doing.
Some times I see people get tired of throwing paint and me and try to just rush me... like I'm supposed to just wait for them to be on top of me and yell surrender or pop one point blank. Then they get surprised when I open up on then and they get hurt. Then that's usually followed by a sincere "I'm sorry if I hurt you, but what where you thinking?"
I try to use the back up and shoot tactic when possible. If it's really not possible and I know I have not been seen, I will call out surrender but you can be sure I'm aimed and finger is on the trigger. Not to be mean, but surrenders have backfired on me more then anything else. So with time, I'm a bit less incline to save other people pain by taking it my self.