I don't really know, but this sounds kinda logical to me.
When you throw the ball, you would essentially want to release it at the highest velocity in your arm motion. The follow through is just the energy going somewhere. So you would have your arm accelerating, reaching it's max speed, the ball comes out in there, and then it decelerates.
I just think you might be carrying too much speed past the point of release.
Do you do it when you're not throwing hard?