The advantages are a cleaner burning engine, less stress on pistons and
connecting rods due to peak pressures occurring later when the rod has more
mechanical advantage on the crankshaft and lower cylinder head temperatures.
CO production will also be lower to non-existent.

The engine will burn plenty clean enough ROP.
Stress levels are well within limits ROP
Cylinder temps are well within limits ROP
CO? So what! Goes out the exhaust.

The only advantage to running LOP is an engine that runs at a lower BSFC.
Which increases range, not so much by decreasing fuel consumption, but by
slowing the airplane down closer to best range speed.

Walter Atkinson is a dentist. He once told me that my IO-520D was more like
a Wright 3350 "Cyclone" engine than a O-470U. He is in well over his head.

Karl