If in fact the debt limit is not raised well beyond the August 2 target date, and the economy suffers the severe blow that experts, Democratic politicians, and most Republican politicians believe is likely to happen -- the dissenting Republican politicians such as Michele Bachmann, Steve King, and Louie Gohmert (and other insiders) will not, in fact, admit that they were wrong about it. Instead, they will blame Barack Obama for implementing the debt limit badly. And they will do so no matter how he implemented it (I'd say that would include if he did it precisely how they had advised, which would be true, except that I believe their position is mathematically impossible, so it won't be happening).
What's more, and this is only slightly less obvious and slightly less certain, they will almost certainly not be penalized within the GOP for being wrong. Indeed, what's far more likely is that if, as virtually all economists and budget experts currently insist, failure to raise the debt limit causes economic disaster, the likely effect within the GOP will be to enhance the prospects of those who claim that the experts don't know what they're talking about -- and any post-limit disaster will be considered yet another sign that the experts don't know what they're talking about.