The word that comes to mind is not so much presumptive as presumptuous. I'm not a Bernie Bro, but let this play out. Potentially it's only another day or two, anyway. There is this quiet narrative that superdelegates who have expressed support for a candidate are held to "no backsies". And that is clearly not how the process is defined, and Bernie has had no success is getting this across to people. He may be mistaken in how his strategy will play out, but it's simply a lie that his viable path to victory is now, ahem, "foreclosed".