wrote

If the wisdom that you have to get the oil up to 180 F is
true, then how do they explain preheaters evaporating water when they
don't get to near that temp?

If you put the engine away with the oil dry (from air runs) and you keep the
engine a constant (or nearly so) cooler temp, you will not have condensation
forming inside the engine. No need to evaporate the water out, if there is
none in it.

The main thing in the oil that necessitates changing it
regularly is pure and simple carbon particles that make the oil
slightly abrasive, sort of like a mild lapping compound.

False. Oil filters clean the abrasives out of the oil, if they are changed
regularly. I have heard some say, that if they can't change the oil on
time, change the filter, and more often than called for, if they can. Oil
needs to be changed because of the changes in PH, viscosity, and additives.

Diesel engines in some large boats (Navy and other commercial crafts that
are always on the move) never have the oil changed. Never. They just check
all of the oil chemestry, and put it back to where it should be (ph
especially) put some more of the additive package back in, and keep changing
filters. PH is very important.

And as for "blow by", well, a good engine has little or no
blowby.

It does not take much blow by to leave a lot of water and other gunk behind.
All engines have blow by. They should not have excessive blow by.
--
Jim in NC