Was a debt ceiling hostage scenario unavoidable?

Jonathan Bernstein thinks I dreamed up an impossible counterfactual in suggesting that Obama might have refused to negotiate over the debt ceiling:

The ability of the president to force Republicans to separate deficit limitation from the debt limit, in Sprung's (or any other) scenario, is limited to the threat of invoking the 14th Amendment and running through the limit. Whatever the Constitutional status of that threat, I would have argued that it contained grave, serious threats to the president. Invoking the 14th now, or next week, after well-demonstrated GOP stubbornness and immanent danger, is one thing; declaring the debt limit unconstitutional by executive fiat right after a GOP landslide would have been seen by everyone except core partisans as an illegitimate overreach. Instead of constant reminders about presidents of both parties supporting increases in the debt limit, we would have been subject to constant reminders about how presidents of both parties accepted the limit, even when Congress delayed or attached stuff to it. At least that's my best guess. In my view, it would have handed the Tea Party House a huge gift: they, and not the president, would have been the reasonable ones.