Vertically uneven brake pad wear

[timothy]

MikenOH: The rotors are a year old and still have a lot of life remaining. The top of the pad is more worn so I don't think we can blame a lip on the rotor -- that would angle the pad so the bottom wore more.

Stephen: An increase of rotor linear speed from pad top to bottom makes sense but from what I read the pistons should keep the pad flush to the rotor and ensure even radial wear. I did not see a radially uneven wear pattern after other track events.

If only one pad I'd suspect a cocked piston yet it occurred on both the left and right inside pads. Could inadequate brake cooling cause this? Or maybe I just have bad luck and both calipers need to be rebuilt.