I mentioned this during last evening's live blogging of the VP debate. The plan can't cut as much as it claims while also being revenue neutral. Sorry, but it's a fantasy. I was going to expound on this today, but Josh Barro's got it covered.

Mitt Romney's campaign says I'm full of it. I said Romney's tax plan is mathematically impossible: he can't simultaneously keep his pledges to cut tax rates 20 percent and repeal the estate tax and alternative minimum tax; broaden the tax base enough to avoid growing the deficit; and not raise taxes on the middle class. They say they have six independent studies -- six! -- that "have confirmed the soundness of the Governor’s tax plan," and so I should stop whining. Let's take a tour of those studies and see how they measure up.

The Romney campaign sent over a list of the studies, but they are perhaps more accurately described as "analyses," since four of them are blog posts or op-eds. I'm not hating -- I blog for a living -- but I don't generally describe my posts as "studies."

None of the analyses do what Romney's campaign says: show that his tax plan is sound.