Oil Trading Conspiracy -- To Reduce Prices?

A while back, I talked about a conversation I had with a friend of mine that prices for oil were set $20 dollars or more above the natural clearing price because a few oil traders controlled the market.  I argued in a long post that this was absurd, and might be possible for a few minutes in the trading day, but over multiple years it would be just impossible either to store the extra oil supply or hide the efforts to suppress supply from thousands of sources.

Well, another argument I made is that buyers in the oil markets are big boys too, and would not tolerate paying $20 a barrel too much for years or even hours.  After all, it was silver buyers and the exchange owners who stopped the Hunt's famous attempt to corner the silver market.

Anyway, one proof of this latter proposition is this

The alleged manipulation occured during the so-called "Platts window,"
a 30 minute interval at the end of the trading day when the energy
publishing firm Platts pulls data used to set prices for other foreign
and domestic crudes. CFTC said Marathon tried to sell oil below market
prices during the window in order to get a lower price set for oil it
intended to purchase.

Again note the timing -- trying to influence the market for minutes, not years.  If companies like Marathon are willing to risk criminal prosecution to get lower oil prices for purchase, they certainly are not going to sit back and tolerate a multi-year manipulation that raises prices $20.