[HoustonCurmudgeon]

You are correct as far as you go but have failed to even mention limited supply drawn from the same pool, where the independent gets their supply and who refines it to begin with. After 30 years in the oilfield I can't tell one barrel from another, nor can anyone else.

[NovemberCharlie]

Maybe I'll work that in. The reason I put this together in the first place was that a few years ago someone was posting this thing every week.

Then they seemed to stop as soon as I wrote it, so it never got posted. Figures.