CG, that system did not work for me. Here is my problem, with chucks, you are usually shooting up or down hill, really throws a monkey wrench into the system. So, knob twisting worked better for me...puts me closer on my guessing with the wind, up hill angle, etc. If you have the whole chuck to shoot at, it would be very different, but more often than not, you have a head and shoulders as a target.
We would dial in the yardage, estimate the wind value(adjust with our best guess), then fire on the chuck. Amazing how close you can get on first shot, we call our shots, not shoot center of mass.
Good luck!
