You are right there is an emotional bonus when the anger feels justified, and you are right to be skeptical when I say that in a fight one of the things I'm going for is to feel stupid for being upset. I'm probably harder to convince I'm wrong when I'm angry, but still I know it's then that I need it most. The best outcome is when the problem simply disappears because I realize it was only in my head. I'm not saying I'm capable of pulling this off everytime I should. In the fight I mentioned, my friend was actually pointing out that I blew the thing out of proportion, and didn't bother convincing me about the details.

I understand now that what you mean by losing a fight is admitting you were wrong. This is indeed embarassing, but it's also your victory over yourself.

Your idea of arranging to lose a fight sounds dangerous. I once did that with a coworker. I admitted I was wrong just to end an argument. When the coworker later found out I didn't really believe I had been wrong, there was no longer enough trust to solve the problem in a discussion.