I am sure most experience lifters know that not going to failure, every set, never means the any one is not working extremely hard on a exercise. And in return reap the benefits of more muscle size and strength.
Watching the video's of some of the Pro's, and other top BB'ers, it becomes quite clear that there are at least 1 or 2 more rep that could be preformed if true failure was their goal. Watching them workout in person, if becomes even clearer They might push the failure button on the last rep, of the last set, for a given body area at certain times, but most likely not. And some Pro's may just do it for the video audience, not in real time workouts. After all, BB'ing is just another form of show business.
General rule for success for the top guy's are middle range fast reps and cheating. Add to that, shorter workouts per body part for some. Good Luck.