Because I am in a mood, I will. So, diesel is a byproduct of gasoline production. It was near free to make until Ultra Low Sulfur mandate. It was cheap. The big oil decided to charge per BTU, that is why diesel got so expensive. So, if fuel is BTU driven pricing, why is mid grade and premium more expensive, excessively so? There is no more BTU that regular gas, just higher octane which is just the resistance to detonation. They just get to screw everyone both ways. Rant done.