Cutting chicken, especially off of the bone, is difficult to do with any consistency. At the restaurant I ran we had one prep cook specifically for Chix/Meats, meaning only two people needed to be VERY GOOD at it(seven shifts per week needed to be covered), and would cross train in case of sickness or vacation. That achieved consistency and since he was cutting 120 to 240# of chix from breast to small pieces saved a lot of money by minimizing waste and labor. You may already do this, but calling prep in the morning and having everything split consistently so the prep cooks are always doing the same thing creates consistency and speed.
Of course, you may already do all of this, but when you say having everyone do it the same seems to mean that a lot more people are in this process than may need be. Also, when you call prep in the AM you need to be accurate and prepare enough to at least begin lunch the next day.