I don't want to answer for him but IMO visuals is when you know the shot is on. You can do this in many ways. You know the part in your brain that when you look at the shot knows it's on? That is visuals. When visuals are correct (and practiced until rote in a way you can trust) math makes absolutely no difference.
Yes, physics still applies, but the CB and OB don't care if they make a 7/16 ball hit or a 36.95 degree cut. Sure, the math is there in the background, it can be used as a proof in a way, but it's not the math that makes the balls. Math, aiming, fractions, angles, etc are more just there so you can shut your ego up to a point that your subconscious can execute a shot. Some people need to convince themselves a shot is on more than others. Some just trust the visuals.