http://factcheck.org/2012/10/dubious...-declarations/
Fact Check is the best site for debunking things like this.
To add some context: As stated n the debate, Romney's tax plan also relies on economic growth, and not just deduction cuts, to drive tax revenue after his proposed cuts. You can say that it's wishful thinking, but looking at the the historical numbers you can easily argue that any tax plan relies on economic growth to remain viable. As Bond and I have cited multiple times, GDP drives revenue, not individual tax rates.
Overall, I think Romney's most effective claim, and what separated him the most from Pres. Obama, were his statements on bipartisan governance. Listening to people in the middle, I think that resonated with independents.
As for Pres. Obama, he didn't look like he wanted to be there, and missed several opportunities to swing at lobbed softballs. Dems better hope he was simply tired, and that this isn't a strategy. If it's strategy, he's in trouble.