You might see a class action against the etf manager if this keeps up. They had to have known this was a major risk, but from what I've read , they downplayed it.
Chinese stock ETF's did the same shit back when Shanghai was was moving. I don't trust ETFs, they should not diverge this much even when volatility is high.
Incompetent managers trying to outsmart the market and got burnt. The purpose of the tracking ETF's is to track the underlying market as closely as possible, not to outperform them (people trade both long and short sides). They need to hire someone who knows math and sort through the interdependences of all their instruments.
oil is in contango, as someone noted in the first comment to that seekingalpha article. The most recent rollover made the front month contract jump almost $3. You can't have a stock with such discontinuities. The best way to evaluate USO's performance is to look at the price of the current front-month contract (CLK7) over the same time period.