The choice of feedstock for any refinery is based on a vast number of considerations. There are very sophisticated computer programs that do that sort of planning. But the trade-off between taking western crude and available crudes from other sources like crudes really comes down to the investment at the refinery.
As Mr. Quinn said, there would be a need for investment in refinery capacity, within certain capabilities, to produce gasoline from heavier crudes. That's the real question to be answered, which we can't really break down and analyze in this meeting. It's not just a choice of closing one tap and opening another. Investments would have to be made at the refinery to accommodate heavier crudes.