just to throw this out there, Menthol has a broader range of air fuel ratio that it will make power. So you can run rich and the performance does not suffer all that much. But the richer it is the more fuel you get in your oil. Gasoline has a much narrower air fuel ratio so if you are rich it runs like crap.

https://www.racingjunk.com/news/weather-considerations-for-racing-methanol/