I'm going to borrow a line from the Republican Senator/robot Marco Rubio: “Let's dispel with this fiction that Barack Obama doesn't know what he's doing. He knows exactly what he's doing.” Except I'm saying it about Donald Trump.
A debate between him and Sanders would be a heavyweight fight. The Republican Nationalist and a Democratic Socialist debating about the issues without the input of any "establishment" candidates? It would probably be the most viewed debate of all time! Any network could easily make the $10 million back.
It is also the worst thing that could happen to Hillary Clinton. Sanders will go out and show the Democratic superdelegates exactly how he will attack Trump, and Trump will not be able to deflect off the issues and make character attacks. Every moment Clinton is on TV defending herself, she is not using the platform to attack Trump. If she is indited by the FBI after the convention, but before the election, she could seriously lose to Donald Trump. Think about how tough it would be for Clinton to talk about national security in a world of cyberattacks when her solution, when she thought she was being hacked, was too unplug the computer and hide it from the appropriate cyber security officials.
I think Trump has a long game. As crazy it sounds he wants to lose, or at least not beat up on Sanders with cheap shots. He wants Sanders' voters come November, and I don't care if you think he won't get any. I say start the bidding at 25 percent over or under, just another reason Clinton could lose to Trump. If the Democrats want to win in November they must reject Clinton, ask her to step aside and take time to address the email issues, and try and keep it from affecting Sanders' candidacy. She needs to endorse him and help him at all cost, including financially.
If Sanders throws a knockout blow to Trump, he can still earn the nomination from the "establishment" simply by showing them having a person whom stands on solid moral ground can avoid the food fight about character. We could be seeing the first of the true presidential debates on the 21st, at the very least I hope both parties treat it that way. It would be sad if the person who hasn't secured the nomination was the one who acts more presidential on the stage.
We might never know and it may all fall apart, as things are wont to do, but as citizens, don't let anyone tell you just because Sanders doesn't know his future that to debate is futile. The establishments are dead and the new political dynamic that will surely only grow exponentially during the next election cycle at all levels of government are represented by these people. We must have vigorous debate more often so the citizens are never tricked by those masquerading to protect us.