My first tattoo i went to get i wanted it placed where i cut myself most to stop me doing it, he refused. I have it on the other arm and have to say i am glad, because i probably wouldnt have stopped then, tattoo or not you just find another place.
I see your point though, and i must admit the pain is a little of the reason i get them and yes when things have been stressful for a while i have craved a tattoo just for the pain of it.
But the real fact is its nothing like. Your getting a tattoo for the appearence not to release pain or emotion. (in most cases)
Will x