Depends on the situation. If you have a lump of wood you can throw in front of the tire, by all means, won't hurt. I have seen people winch themselves towards the vehicle they are trying to rescue (snow/ice) and I have seen vehicles pull without choking the wheels. The simple answer is, winches are slow. Winch the person that needs help and if you see your rig doesn't have the footing (is being pulled) try and chock the tires or tie your rig to the rig/tree behind you. Generally its NOT good practice to tug along using the motor to help the winch (if your winch has adequate pulling power and isn't getting the vehicle unstuck, something else may be wrong like it's snagged) but sometimes a little bit can be ok, just be careful. Each situation is different. If you are winching standing still, I personally keep it in park.
