http://www.adarq.org/forum/strength-power-reactivity-speed-discussion/article-optimization-problems-in-training/
Edit: To give an answer more tailored to what you actually wanted to know...
Your question suggests time of rest between sets to be the deciding factor on whether one gains mass or not. That is not the case since "calories-in minus calories-out" determines whether you gain or lose bodyweight.
Provided "calories-in minus calories-out" matches with your respective goal optimal rest times will vary with the rest of your training parameters (sets, reps, exercise, etc.). For example if sets, reps and weight should stay the same, rest times would vary and decrease as indicator of progress. In other cases one might stick to similar rest times and another variant is to not care about it as long as weight/reps/sets goes up.
So in short: It depends, but nutrition will decide whether you gain mass or not.
I realize nutrition is a huge part of it. But what I'm trying to ask is, let's say theres 2 completely equal guys eating the exact same diet and both doing the Bench Press. If one's primary goal is building a bigger chest/triceps, and the other's primary goal is just get stronger upper body, and limit as much mass gains as possible, would there be a different way of doing the exercise for each?
Yes. Im not going to get into diet. Thats not my thing.
But training wise theres a huge difference. As I would do it, guy building mass would do 2-4 sets of 8-12 reps with short pause between sets, ie. 60secs.
For the guy wanting strength gains with minimal hypertrophy Id do 3-5 sets of 3-5reps with relatively long pauses 3-5min.
Again everything depends on what kind of exercise, main or support, the person, effort put into the lift and so on. I always start novices with hypertrophy, standard 3x10, p60.