IF MotionFrameCounter == 0...

* If there's a piece below 1, it stops.
* Else If piece 2 is below 1:
	If 2 is going to stop, stop 1 too.
* ELSE, test piece 2, and if it's going to stop, then piece 1 needs to fall.

test 2:
* If we got here, we know whether or not piece 1 stops. In fact, we may have already tested 2 and are done.
* If there's a piece below 2, it stops.
* Else if piece 1 is below 2:
	If 1 is going to stop, stop 2 too.