In other words I think this is what coaches are telling their students when teaching the shot process. When you stand behind the shot, before you get into position, you are using the working portion of your brain, which has limited capacity. You confirm your tip placement on the CB, and your speed, and visualize the shot. When you get into position for the shot you then switch to your procedural portion of the brain, which is automatic with no thought process, to just execute what you confirmed while you were standing. If while in position for the shot you start second guessing what you're about to do you then you switch back to the working portion which can only usually only focus on one thing at a time. If you're in position and you start thinking about your tip position, speed, etc you are overloading this portion of your brain and you will usually miss.