I think at least one of the issues is that other AAA countries/entities simply don't produce enough debt. It' not just that we're AAA, it's that we produce so much AAA paper. The AAA bond market gets so much smaller is the issue. That's my understanding, but I'm no expert.

I think that is largely why this won't have that much of an effect, there isn't a replacement for that much money that is AAA. The "cure" (crowding into what is left) would be more painful to the bond market than the "disease" (us).