So you have the Saudi's and Russians............buying depressed oil stocks, talk up the price of oil with fake meetings and production freezes. The sell the stocks at the higher prices (hence the diconnect between the price of oil and stock prices).
They short the stocks through their surrogates (Goldmanand others), announce the breakdown of talks, oil plummets and they fill their depleted coffers). Easy peasy.
But what do I know, I am just a dumb retail investor.