I'm going to take it easy on you because I'm a kind person, but your
advice left a little to be desired.
First of all, it's a great idea to shut off the electric, unless
it's a gas WH, in which case, the gas must be turned off.
Secondly, it's a bad habit, not that I haven't done it before
myself, to mess with the relief valve at all. Those things are touchy,
and just fooling around can cause them to drip. You advised that the
relief valve be opened before draining the tank (at least down below the
level of the RV itself). Won't water come out through the relief valve
if you do this??
Thirdly, and this was especially interesting. You said that he
should rock the water heater back and forth. How do you rock a water
heater back and forth if it's still connected to the piping?
Fourthly, since he's winterizing a home, it'd be a bad mistake to
shut off the cold water inlet. That valve would hold water that could
freeze and cause a leak. The cold water valve should be opened as the
Other than that, your advice was just fine.