Bore Honing Without Engine Removal

[model 10]

I don't think they are talking about operating at low power in neutral for hours on end. However going to high power in neutral is silly, it doesn't do anything. You need to go to full power in gear, for a moment anyway, to do anything.

[a64pilot]

Well it will actually blow carbon off of the exhaust valves, just from them vibrating.
It’s the puff of dust you’ll see from an engine even gasoline that is pushed to redline, one that usually is driven by Grandma.

However I agree, I don’t see it accomplishing much, and has always confused me.
I ASSUME and you know the root words there, that they must mean low RPM as in idle or a high idle, or they would surely say if low RPM cruise, increase throttle to full for one min or so?
Why put it in neutral unless your already there and can’t realistically put it in gear?
I think this is for the people that regularly charge their batteries at anchor, not for those cruising at 1500 or so.