I have been thinking lately that the plan might actually be to force Bernie as the nominee, creating a scenario similar to Corbyn's defeat in the UK last December. The party establishment is shown to be ineffective to its owners (they can't even rig their own primary anymore man wtf?), while simultaneously alienating moderate Ds by allowing a socialist takeover of the party. Then in November the socialist hijackers are decimated in the general, leaving both wings of the American left in ruins, and unable to mount any resistance to Trump in his second term.