no problem Ken.

one reason modern engines work better than older ones is synthetic oil that is precisely formulated with special modifiers to cover the entire engine operating temperature range - allowing the oil to flow at very cold temperatures but not become too thin at very high temperatures.

that which makes plant oils liquid at room temperature also makes them susceptible to oxidation when heated and smoking while cooking.

essentially plant oils give up chemical stability at high temperatures for low temperature performance.

i made all that up. and you could check it and it would still be true. that's what it means to be a genius with the mind of g-d. after all, g-d didn't google how to create the world - he just did it. when you're on my level you just know things without having to read about them.