This a great, if long, discussion. My two cents: the more you learn and practice, the better. The more you diversify your repertoire of skills, the better, as long as you don't dilute a few good techniques that work for you with a variety so large you can't remember any of it in the heat of battle. One guy earlier on said it best: you have to keep your head, be aware of your body and your situation, and then apply what you know when the opportunity presents itself unless you can make the opportunity. Many street fights degenerate from nice-looking moves into full-blown brawls as soon as the adrenaline flows and someone gets off balance. No dojo will teach you street techniques like ripping mouths or throwing dirt in someone's eyes, but that stuff happens in a real fight. Because there are no rules except do what it takes to win. I saw Royce Gracie beat that Russian judo champ (name?) just barely in UFC. It was a long, boring grappling match that would never happen on the street because the guy's buddies or the cops would have shown up. Street fights are all about avoiding them if you can, then ending them quickly if you can't, and then getting away when the getting is good. Like fighter pilots learn, sometimes the best opportunity is to bug out with your life intact and fight another day. Tell the story of your hairy escape while you are in a bar with your buds, instead of telling the story of your loss while you are in a hospital bed. Pesonally, I like the bits of different things I've learned -- a little judo, a little TKD, some Kung Fu, some boxing, some good old fashioned bar fighting, and now Shorin-Ryu. I'd like to learn BJJ but I'd probably get hurt training and I'm too old and have a job. So I focus on a mix of striking and grappling techniques that work together for me and my body style. I know I will remember them when the adrenaline starts pumping and some dude won't leave it alone.