Romney's Tax Returns: What the hell?

I find it just amazing that Slick Willard Romney didn't have a plan in place for the inevitable demand that he pony up his tax returns for at least the last decade. This stonewalling is positively Nixonesque, given the level of disclosure that has become the norm in American politics. But the merits of the right of the American people to know about the financial status of a presidential candidate aside, the political ineptitude here is really remarkable. Given what even members of his own party are saying, you have to wonder at this point if Romney can even go forward as the presumptive nominee. Is it conceivable that his candidacy will simply collapse? It's hard to imagine, but it's also hard to imagine how he thinks he can go forward with a campaign that says, "I don't care what you the people think; I'm not telling you this stuff that every presidential candidate tells you."