How much information have you read about detonation, mixture etc. that did NOT originate from APS? It is always wise to gather information from multiple sources. There are a few critical areas (particularly chemistry) where they get things very wrong. Even references to "the laws of physics" when everything they are referring to is chemistry.
I have no doubt many people run their engine LOP without problems. However, the APS attitude where if you DO have problems it means the mechanic dropped a plug, or it was a manufacturing defect, or you simply weren't doing it right concerns me.
They claim science, but I have never seen anything from them that actually looks like science. As far as I know none of them have science qualifications.
(If you're wondering what real science might look like, try some of the NACA reports. They have detailed descriptions of the tests that were done, exactly what was measured and how, the results, conclusions etc. Enough information that someone else could re-run the experiment to verify the result.)