kllcws

toss this around..can you split the load of somthing to roll forward and backward. now catch the force of the wheels pulling each way with a mechanical device(chain,driveshaft or somthing) you say what does this gain you? how much power now does it take to move this by adding power to the mechanical device? you are now no longer moving this load by overcoming gravity's pull, you are moving it by breaking the balance of forwardd and backward forces.