Breaking is the most important shot for table domination in most pocket billiards fame.
Having a strong, controlled break is at times, the determining factor in whether you win or lose a match. It can be assumed that speed equals energy when striking a cue ball, therefore the more speed, the greater the energy when striking the rack. The more energy transferred to the rack the higher the probability that you will pocket a ball.
In my opinion, this is essential to winning.
For me and most of my friends, working on improving our break was nothing more than trial and error based on guess work. We never had a point of reference or measurable goal. How would we know if a different stance, grip, bridge or cue is making a difference at all other than a few lucky rolls?