Poyney,
I suspect it is people hedging their bets that the trial plant won't work, locking in a profit and reacting to the news that China will reduce its fuel subsidies and Suadi Arabia will increase production. If more countries reduce their fuel subsidies then demand and therefore the price of oil may decrease. It may also take the speculators out of the price of oil.
P.S. I know what you mean about trailing through heaps of posts.