The price signal at issue is the way that the WTI (West Texas Intermediate) oil price benchmark has diverged so greatly from the other three, Mars, LLS and Brent.

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The most obvious is the price of the American oil benchmark, West Texas Intermediate (WTI).

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Bakken crude even trades at a discount to West Texas Intermediate (WTI), the benchmark oil for the US set by prices in Cushing, Oklahoma.

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In November, a pipeline deal was announced between Enbridge and Enterprise Products Partners, causing West Texas Intermediate (WTI) oil prices to jump.

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While has traded upward, West Texas Intermediate (WTI) is much cheaper.

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If ExxonMobil is looking at a shortage of sweet-light in its mid-western refineries, they can go to the futures market and buy a few weeks supply of West Texas Intermediate (WTI) for delivery in 60 days.

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