I agree with you including the part about newly rebuilt motors having a bit more contamination due to gasses.
Needless to say, I don't agree with the floor it idea. I've never heard any car maker recommend it and one can safely figure that the average owner is not going to do this to their brand new car unless told to do so by the car maker.
The piston travel is going to be the same no matter if the engine is at idle or 6k RPM. I also have to disagree with any aircraft analogy. Aircraft engines use different metallurgy, different oils, and operate under completely different conditions.
Airplane engines are usually idle, cruise, and full power with not much ever going on between idle and cruise. Even compression figures are far different than an auto engine (much lower).
There's also another glaring difference between automobile and aircraft engines.
Sixty-five percent of full throttle on a Cessna is not exactly an abundance of high RPMS (note that cruising RPM band/red limiter in the pic) and exhaust gas temperature is very critical during an aircraft engine break-in period.