The benefit of the Keystone pipeline is that the gulf refineries have a lot of excess capacity to refine heavy crude that was previously fulfilled by heavy crude from Venezuela.
Gasoline consumption in the US peaked in 2007 and given the increasing CAFE standards, gasoline usage will continue to fall while it will rise in other parts of the world.
We are exporting record amounts of gasoline and diesel. And given that demand for gasoline in the US will continue to fall, the only way for the oil companies/refiners to stabilize the price is thru exports.
Export baby, export.
My post illustrates the difference in safety between moving oil via pipeline vs. railroad.
The origin and destination of the product is irrelevant.