Far be it from me to mistake a debate for a “truth-telling contest” but it’s worth mentioning that Romney has been very specific about his $5 trillion tax cut plan, and not at all specific about how he wants to pay for it.
Brian Beutler talks to the nonpartisan Tax Policy Center:
Romney’s objection is that the $5 trillion tax cut is only one half of his plan. But crucially, it’s the only part of his plan that he’s detailed with any specificity.
The $5 trillion from the nonpartisan, independent, Tax Policy Center. It’s an estimate of how much cutting everyone’s tax rates 20 percent below where they are right now would add to deficits over 10 years. That gross tax cut figure is not in dispute. Romney’s complaint is that it only accounts for one big piece of his tax plan. But what’s still unclear, perhaps more unclear after the debate, is the other big piece: how Romney plans to pay for it.
“[T]he governor repeated his vow that his tax rate cuts would not add to the deficit,” tax expert Howard Gleckman wrote on TPC’s blog after the debate. “And he said high-income households would pay the same share of taxes as they do today. And middle-income people would pay less. So, how will he finance the rate cuts? The poor could pay more, I suppose, though that’s unlikely. The only other solution: The tax cuts would have to pay for themselves by generating a huge increase in economic growth. But these big supply-side effects are implausible at best.”

Actually last night I heard Romney enunciate a very clear and specific rationale for how his proposed tax cuts would remain revenue neutral. GROWTH. After spending cuts and closed tax loopholes, economic growth caused by decreased taxing and regulation would make up all the difference.
I’d really like to see an analysis of how much US GDP would have to grow to fill that gap exactly. 8% 15%? 30%?
Just like how growth totally paid back all the lost revenue from the Bush tax cuts. Super dynamic or whatever!