And once again---"THE SECRET". This is something I never tire of talking about, because it's such an essential aspect of good mechanics, and all pitchers need to learn and master it. Roger, you hit it right on the button---the pitcher starts the process when s/he drives off the lower half of the body, using the legs, the hips and the torso in one continuous and rapid-fire motion, thus getting more power behind one's pitches; that's where the momentum comes in. I'm really surprised more coaches aren't aware that the lower half is the real key to a pitcher's power! You don't throw with just your arm; you have to get the whole body involved.