I am wondering why so many people erroneously assume that (a) fat inhibits fermentation, and (b) sugar increases fermentation.
When I tell people that sugar (in concentrations above 10-12%) inhibits fermentation because of its hygroscopic properties, they look at me funny and dismiss it (although perhaps the word "hygroscopic" is the cause for that funny look). Their logic is always: "yeast loves sugar. More sugar = happier yeast. Happier yeast = faster fermentation".