Well, sorta... The idea is that a mob with a big enough hitbox can be moved by multiple pistons at once... It's already been done with llamas, I just wanted to make a practical one that actually works on SMP.
Seriously, go dig somewhere else. If you really have to dig somewhere why don't you go the the desert where it's actually useful and you don't ruin our minecart tracks! There is no reason why it has to be at the lake!