No, getting sore is an indication of your "total lift" - that is the sum of the amount lifted and how many times. For example, deadlifting 300 pounds 6 times gives a total for that set of 1800 pounds. The greater your total lift, the more likely you are to be sore; and since you can lift 70% of your maximum lift far more times than 90%, you will usually get more sore doing endurance training than doing strength.
This is trivially easy to falsify. Try lifting your absolute maximum once, and see how sore you are immediately after and the next day. Try lifting a tenth of that twelve times, and see how sore you are after that. If you don't bring your muscles to fatigue, you're not going to be sore even if you rack up a total lift much larger than you would in an ordinary workout.
That said, once you've gotten your body acclimated to regular weight training, you'll become sore much less easily, and this doesn't mean that you're not getting the benefits from the weight training
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.
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.