winterizing trailer but still using it in winter.

We have friends who never drink the camper water. Come to think of it I've never seen him drink water. Anyways, he winterizes by dumping a couple of gallons in the fresh water tank and pumping it through the system. He does bypass and drain the hot water heater. You would not damage anything but would take a bunch of water to flush out the fresh water tank if you wanted to drink the water.