I'm struggling to understand how the government thinks that it can get GM in and out of bankruptcy in the blink of an eye. In a "prepackaged" bankruptcy, where there's substantial agreement among the parties, that may be possible. But neither the unions nor the bondholders show any signs of making generous concessions in order to get the other parties to agree. If the government wants to make labor happy--and it seems it does--it can either pay off the bondholders to go away happy, or it can wait for the thing to snake all the way through the bankruptcy courts. That generally takes more like a year than the "weeks" I've heard claimed.
There's no doubt that ultimately the bondholders are going to take a big, deep haircut in bankruptcy. But the fantasy where they quietly accept it while the court crams everything desireable into one company, while leaving a few paperclips and the healthcare obligations behind for the creditors, seems . . . extreme. Indeed, I don't think the government believes it either. I think they're just pretending too, so they can act all horrified and sad when it turns out that the UAW has to make some concessions too.
But I don't expect either group to make concessions outside of bankruptcy, even if they'd be better off not going before the court. Each side seems to believe for its own good reasons that someone else has the moral responsibility to bear most of the pain. They won't take a barely decent deal if it means someone else gets a better one.