as you all know there is silver and gold tracking stocks. So why not oil tracking? Ever wondered why USO is at $60 now? As you know this "tracking" stock followed crude much like GLD follows gold. But at one point there was a divergence. When crude oil fell last year, the fund that invests (supposedly) in crude (physical) and futures contracts had sold out it's positions and somehow never got back fully into the holding (at the price and size) where it was before the selloff. So now people who invested in USO for the long haul are screwed.
USO had too many whacky energy positions. I assume at the last peak USO managers got nervous and diversified their oil position. Instead of correlating close to 100%, it's probably around 60.
I think it happened the way I described the last time oil market tanked they got stupid. They are still employed and presumably drawing excessive salaries while the stupid sheep (US average investor) suffers.