I have heard similar speculations in the Bush era. At the end of the day, it never happens.

There are just a few members of Congress that meet that description, however. They only wield a lot of power when the rest of Congress is divided neatly into two nearly equal parts. The moment actual default becomes a real possibility, the mainstream members of both political parties will briefly form a consensus and kick that can down the road a ways. Just like they always have. Not too far, mind you, because it must remain something they can argue about periodically.

The bad part, of course, is they likely won't do that until we've already done some damage to our credibility.