Swimming and Breath Control - Does Breathing Every 3-5-7-9 Make You a Faster Swimmer?

Swimmers, do you control your breathing rate during swimming sets in a swim practice? Do you follow a breathing pattern, taking one breath every certain number of swim strokes? Do you swim a certain distance and change the breathing pattern each length, such as breathing every 3-5-7-9 by 25's? Why do you do that?