I agree with your last paragraph completely, but I guess I wasn't clear about the "total lift" and soreness bit. I didn't mean a fixed amount of weight, I meant doing your maximum reps with a particular weight - the maximum number of times I can lift 70 pounds is a lot more than 5 times the number of times I can lift 350 pounds. In fact it is more than 10 times as much- 70 pounds by 50 reps (3500 pounds total) versus 350 pounds by 4 reps (1400 pounds total). And the former leaves a lot more aches than the latter.
Well, if you exercise until you can't lift 50 pounds for another rep, you've fatigued your muscles more (deteriorated more myofibrils) than if you exercise until you can't lift 180 pounds for another rep, although you're not going to build your fast twitch muscles as much only doing low weight.
I'm looking for resources on effective weight training for the purpose of physique building. It's an area with a particularly poor signal to noise ratio so I would value pointers from other rationalists. The kinds of questions I would like to answer are:
Edit: I'm vegetarian, and I now realise this is rather important to answers to point three. So far the only supplement I've been taking is soy protein.