I have an interesting side bar to this topic. I was watching the "Modern Marvels" program on the History Channel about the pipeline system for gasoline transport.
All gasoline from all refineries is generic, exactly the same. The seller in Houston puts "x" amount of gallons in the pipeline and the same day the buyer in Chicago, Cleveland, New York takes out an equal amount of gallons. The buyer will then blend in his own additives to his required formula before delivery to the local gas stations. It's all done with the same base but with custom additives.
Well, it was new to me. Class dismissed.[
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