For pure BB'ing it's not so much a question about power and how more you can lift than the other guy. People tend to get caught up in ego training that way. Wish I had a dollar for every guy who's come up to me and ask how come they can bench 50-60lbs more than Joe Gymbag, in a workout, but he's much bigger and muscular all around in the upper body. With BB'ing, it's as much a mind game as it's a lifting effort. For the most part moderate weight, rep scheme of 8-12 and very short intervals between set's (45-60 seconds) are the main workout style of most successful BB'ers. The main purpose is to train the muscle fibers and not over stress the joints, ligaments, tendons, etc. The goal is hypertrophy, not strength so much. Strength will usually follow and develop with a good BB'ing workout. The progressive system of training demands that. This does not mean that all exercises are preformed in the strictist style or each rep is a complete ROM. A looser style does have it's place in classic BB'ing.
That's one of the reasons that a lot of BB'ers will raise the feet/legs of the floor when doing BB/DB BP's, fly's, cable fly's, etc. Reducing the element of other body areas out of the bench and just to focus on the chest and pressing muscles themselves. Lot of guy's will do sitting presses, laterial raises, curls, triceps , etc pretty much for the same reason of a better focus on the region they want to work. Of course much less weight is used for their desired results. Ego training and the amount of weight used is not the main factor. Hypertrophy is. Good Luck.