2) Starting and ground running the engine for a minute or so is the
"worst" thing you can possibly do.

Well, I can believe that running "a minute or so" could be quite bad.
However, I've heard that you should just not ground-run your plane in
the winter, period, which never made sense.

This always seems counter-intuitive to me, since (as you say) the only
way internal engine parts are going to get covered with fresh oil is if
you run the engine.

Given the winters in the Midwest, there have been times when we went
three weeks without getting to fly. I've often wondered what was
worse: Letting all the oil run off the internal parts, exposing them to
corrosion, or running the engine for, say, 30 minutes at moderate RPMs
(say, 2000 RPM) to get everything good and worked up.

The only downside I can see to running the engine in this way (in the
extreme cold of winter) is that the prop can get pretty beat up on a
ground run.

3) Flying for an hour will "clean" the oil (or at least evaporate the
water, preventing acid formation) so that it doesn't turn to acid and
dissolve the engine while sitting idle.

Well, I don't think it "cleans" the oil -- but it should purge the
engine of moisture. And it will certainly lubricate all the internal
parts, which is the only way I can imagine any engine making TBO.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"