I happened to notice a difference in fastball locations between Zack Greinke and Rich Harden. Does Harden go up and out of the zone more by design, since he really throws two pitches? Greinke has a wide arsenal at his disposal.

The gray box is the approximate region of the strike zone, which accentuates the difference between the two pitchers.

x-axis is height in feet, from ground (left) on up. y-axis is percentage of pitches in each height bucket; lines are smoothed