If conviction/emotion/release=bleeding, then I think you're taking the guitar rock hero thing a little too seriously. I've bled a bit in my day on stage, but I don't see the point in pushing a performance to such an extreme that it renders you useless for the next gig. Unless your gigs are so few and far between that it doesn't matter (that's not a dig), where maybe balls-out is more justifiable. I'm just talking, you know... common sense, I guess.
I'm not saying you should cry, I'm saying a little electrical tape can do wonders. The only people that should bleed that much in front of an audience are performance artists, because they crave the attention that much.