He might get away with it; but I hope not.
The fact is that Ryan is and always was a fraud. His plan never added up; it was never, contrary to what people who should know better asserted, "scored" by the CBO. What he actually offered was a plan to hurt the poor and reward the rich, actually increasing the deficit along the way, plus magic asterisks that supposedly reduced the debt by means unspecified.
His genius, if you can all it that, was in realizing that there was a role -- as I said, that of Honest, Serious Conservative -- that self-proclaimed centrists desperately wanted to see filled, so that they could demonstrate their bipartisanship by lavishing praise on the holder of that position. So Ryan did his best to impersonate a budget wonk. It wasn't a very good impersonation -- in fact, he's pretty bad at budget math. But the "centrists" saw what they wanted to see.
Ryan can't be ignored, since his party does retain blocking power, and he chairs an important committee. But if he must be dealt with, it should be with no illusions. Fool me once ...