His logic makes more sense than your baseless dismissal.

MMO is light base stock oil with Varsol added. Simplified a little but that's the basic recipe. Got a too-tight valve guide? Thin oil and solvent may be beneficial. History says it has been in big radials. In fuel? It helps with lead problems. That's a more recent problem with 100LL being the only aviation fuel most of us use. If you don't want to run it? Don't, but that doesn't mean the rest of us are foolish for using it.