User blog comment:MultablokdInc/Impossible idea it is?/@comment-5414390-20121003233109

Okay so if only the person who placed it could edit the speed then that removes the possibility of trolling. However for it to be possible it would have to move the piston a little bit at a time, the only way that this would be possible would be to use effectively the sub-block system and change the rate at which the next 8th is added for the different speeds, being a sub-block system however means that it would be possible to walk through until it was of a large enough size. it also would be incapable of moving blocks in front of it by this method. To make it work then: it would be horribly complex, inefficient, unneccesary and personally I don't see the need to change piston speed.