As I see it, the difference between the two is this. The dry throw, where you go through the moves without the ball, can be useful when you're learning a new pitch---to a point. I much prefer the second one, where you get up on a mound, whether in the bullpen or on the playing field, and throw the ball; you get the feel of the pitch, which is absent in the first go-through-the-motions throw. I remember when I was talking to Eddie Lopat, and I mentioned that I was using the crossfire a lot. He said, "Let's see what you're doing with it---just go through the move." I did so, and immediately he called my attention to the fact that I wasn't getting as much momentum from the stretch as I was from the full windup. This was a case where the "dry throw" was useful; it pinpointed a mechanical problem. Needless to say, we fixed it in short order.