What Romney said:

A book that was written in a way that's apparently pro-President Obama, was written by a guy named Noam Scheiber and in this book he says that there was a discussion about the fact that Obamacare would slow down the economic recovery in this country and they knew that before they passed it.  But they concluded that we would all forget how long the recovery took once it had happened, so they decided to go ahead.  The idea that they knowingly slowed down our recovery in order to put in place Obamacare, which they wanted and they considered historic but the American people did not want or consider historic, is something which I think deserves a lot of explaining, because I think the President’s responsibility is to put people back to work. To get people out of poverty and to help people have good jobs and have prospects for a brighter tomorrow.

Chait fisks:

Not only is it false for Romney to say Obama "knowingly slowed down our recovery," it’s not even true that Obama knowingly passed up a chance to accelerate the recovery. The notion that anybody in the administration believed that the health care law would actually slow down the recovery is complete fiction. It does not appear in the book anywhere and it’s pretty obviously untrue.

Earlier lies rounded up here. At this rate, Romney may beat Palin's record – but his lies are calculating. Hers were a function of being psychologically unbalanced.