CV joint and driveshaft breakage isn't prooving power. The stress on your truck itself is much more than on the dyno. A dyno is a great way of showing and tuning for power. I'm a drag race guy, though I enjoy watching and have broke some parts truck pulling myself. Did the parts break because I was putting down so much power? The answer is no. The parts broke because I didn't have the experience to read the track, and what was going on with my truck. I feel most people that make fun of the dyno only guys just wish they could put those numbers up on the board. To dyno only guys, it's just as serious as you pullers and my drag racing. I say we just support all three for what they are, just a different version of the addiction.