During the health care debate, center-right commentators tended to look skeptically at the administration's commitment to restraining health care costs -- it was a nod to political expediency, they believed, not a deep belief. Sam Stein's omnibus health care reform article has a nugget showing from the inside that this was not the case:

On January 11, the president brought a group of more than a half-dozen union presidents to the White House to remove any lingering doubt. "There will be an excise tax," he declared, according to one attendee.
"I'm committed to doing it," another attendee had him saying. "And I need you guys to be on board."
The crowd wasn't sold. AFL-CIO President Richard Trumka, seated across from the president, shot back that the tax was "bad policy and bad politics" pointing to the percentage of middle-class workers (even the non-unionized) who would be hit. Anna Burger, the executive director of union campaign arm, Change to Win, brought up Deb Lovell, a state worker in New Hampshire and wife of a chronic myelogenous leukemia patient, who despite earning $30,000-a-year salary would see her health care plan taxed under the proposal.
The President conceded that taxing people like Lovell was not the design and promised to look into Burger's point. But he continued pitching the tax as necessary for keeping health care costs under control. "He was persuaded to do health care, I believe, by Peter Orszag [the budget director], not Ted Kennedy [the moralist former Senator]," is how one White House ally put it.

The notion of controlling costs really, truly was a major motivating force for the administration.