There's a huge thing about it on @pharesim's recent post about @jerrybanfield and Witness voting. You'll see @sircork and @themarkymark pointing out valid points that seem to be brushed aside there.
What @berniesanders (props to him by the way) has done is a work-around and easing the symptoms of an extremely flawed system.
An interesting read. Gave @pharesim @boatymcboatface's vote and will be rethinking my other sacred 20 votes. Thanks for sharing.