Disapearing blocks with pistons

When 2 pistons try to push a block so that when both heads are extended the block in the middle will be destroyed if placed on one piston and not the other, works facing both directions, Not a massive problem. If there was not a good explanation I uploaded a bug report to youtube.

Link: http://www.youtube.com/watch?v=_n0MjCOQmek&feature=youtu.be