dpb wrote:
....

Other than heavy coats of enamel or other hard finishes it'll make
little difference--varnishes, etc., are much softer than the wood itself
and don't abrade the surface to create heat, etc., in the way the
friction of sandpaper does.
....
Dangit, that was supposed to read "...and [planer knives cut rather
than] abrade the surface ..."

but somehow lost my intended edit...

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