Torque is force over distance - or the measure of force/weight and the leverage it is using. Not just pure force, but I think from your example you understand that. You would need to use your weight and leverage to turn the transmission which changes the torque ratio on each gear it is using. You are correct that you need power to go with it. You would only have that torque, until the lever went fully down and you fell off, you couldn't duplicate it for the upmotion. Then there is the practicality issue. To replace a diesel engine for long levers where people continuously stand on them to give the vehicle extra torque.

I think to people who say "power doesn't move trucks" - yes it does, power accelerates trucks (and cars). Torque varies how easy it is for that to happen (makes the load feel like less of a burden).