This is actually not true. Even a drop ball is actually thrown with an intial upward trajectory. The force of gravity pulls the ball down at a rate 10 ft per second squared. If you threw with a downward trajectory from the windwill motion the ball would never reach home plate without bouncing the ball home. For an overhand throw leaving a players hand at 7' - 9' ft above the ground you might be able to throw the ball fast enough with a downward plane and still cross home plate before garvity pulled it to the earth. For a windwill with a release point 1.5' - 3' above the ground it is just not possible.Starsnuffer, the ball never travels in a straight line. It may appear to, but in fact to throw as drop ball you need downward trajectory and for a rise ball, upward trajectory.