Very clever, Hans (or should I say Rolf?). The thing is that Pecards is trying to sell something. A something that may have started off, years past, using a harmless animal or vegetable oil which has become more expensive as a raw material than Pecards now want to pay. Mineral oil was not always there in the shoe Trade. It is a relatively new product substituting for another, harder to obtain, more expensive, material. Like corrected grain leather substitutes for full grain calf. To be fair, the possibility exists that they have refined or homogenized the mineral oil that they are using to be better than the unrefined oil. Although I suspect that has already been the case for many, many years. But the point is that you don't know one way or the other. Blindly, credulously, you read it on the Internet and take it as gospel. You're the perfect "mark" for their spiel. Worse however, you pass it on as truth and yourself as the insider privy to truth. Clever Hans, indeed. Without the accumulated experience of having used mineral oil products on leather and seen the results over months and years of use...you're just mouthing someone's pitch. And you're propagating ignorance. Hell, I would wager that Pecards themselves don't even have that first hand experience. Selected testimonials, notwithstanding. I may be wrong...despite 40+ years of experience, times change and ultimately it's just my opinion. But wrong or not, it is an opinion based on experience, not on assumption or pretense.