I shot on that many years ago. It messed with me a bit, because I would adjust for the perceived distance/size of the animal on the screen. Shooting instinctively, I would be shooting over the animal when presented on screen at a distance. When I reminded myself that the screen was 20 yards, and only 20 yards away, I scored better. This was disturbing, as it was tricking my mind and affecting my normal shooting. So I quit shooting with my compound buddies. If you remember, 20, 20 and only 20 yards, you'll do better. But is that really the way you want to practice?
Don't get me wrong, it's fun, but a bit disruptive to a regular routine.