Michael Barone is asking:
The most visible case of unpreparedness in South Carolina this week was Mitt Romney in Monday night's debate, when he was pressed to disclose his income tax returns — an issue he should have seen coming. But Romney hemmed and hawed, visibly uncomfortable, and finally came out with a new commitment to disclose them some time in April. He compounded his problem after the debate by volunteering that his tax rate "is probably closer to 15 percent than anything" and characterizing his income from speeches as "not very much" when, according to disclosures he has made, it was $374,328 between February 2010 and February 2011. These are answers that would have been shouted down in any genuine practice session. One can only conclude that Romney's advisers didn't press him on the issue and that he didn't press them to press him.
He follows up here.
The Dish 