Von at Obsidian Wings lets Reynolds have it:
In answer to your question, Professor Reynolds: Yes. If the US Government defaults on its obligations, the US will be forced to run a balanced budget. This because no one will lend a single dime to the US. Kinda like Zimbabwe. Which is not a good thing. (Ask Zimbabwe.) By the way: I don't know what you were hoping for, but I don't think that Bruce Bartlett's response to your "idea" is intemperate. He's pretty much right on. You're suggesting the equivalent of: "If we kill the patient, he'll be cancer free!"...Do you expect a sensitive correction?
Stan Collender, Bruce Bartlett's blog-mate, adds some helpful analysis:
[T]here's no guarantee that spending would be cut as Reynolds is assuming if the U.S. defaulted on its current debt and found itself unable to borrow. Tax increases would be at least as likely.