The most interesting part of this debate came early on, when Elizabeth Warren essentially told the world that she was in complete agreement with the Sanders agenda, but was a more competent alternative. So much for the unity candidate approach!
For such an ostentatiously brilliant woman, this was an extremely stupid strategic move. The Bernie Bros are not going to desert their man and support her because they admire her policy fluency; in fact, they despise her affection for wonks. The moderates, on the other hand, have no reason to vote for someone who openly disagrees with them on everything. Where does she go from there?
Warren is basically making the case that she should be the junior member of the progressive dream team, and that she should be in charge of policy and personnel. That would make sense, and might well happen. As an argument to actually lead the ticket, however, Bernie with brains makes no sense at all.