Running a typical NA engine slightly ROP is not exactly good for it. If you notice a good CHT gauge will actually show ROP running the hottest point (usually 50 ROP will yield peak CHT). EGT isn't the best indicator for wear upon the engine.... and some engines that run LOP don't quite evenly distribute the fuel/air to each cylinder either. LOP does not run hotter... CHT and ICP (pressure) starts to fall drastically... detonation is almost impossible LOP... however possible slightly ROP....ICP is an important bit of information often overlooked...especially in certain MP/RPM settings

There are a lot of myths in the aviation world... shock cooling is not as common as people think it is... (in order to shock cool an temps must drop around 500-600 degrees in a small amount of time) - Bob Hoover has feathered both engines in a redline dive and yet never had "cylinder head cracks"... go figure...

GAMI swears by LOP....