Not saying they are they only settings available. Just alluding to the over square myths that seem to be around.
Are you saying POH figures WILL cause damage?
Trivia,
Charles Lindburg was "attached" to a P38 Sqn in WWII and suggested different mp/rpm setting in an attempt to increase their range. Confirmed theory with engineers and returned from a sortie with huge increase in reserve fuel over the other pilots.
Ps for the life of me, don't know why I quoted you in last post? Bloody iPad keyboard!