If the reporting is accurate, the anecdote is not just surprising but also telling. A substantial amount of skepticism, perhaps even within the White House, existed about whether the health care legislation did enough on costs. Yet the cost curve in health care is bending more drastically than even I believed possible in the fall of 2009. That's because the collective impact of the legislation's individual measures, along with similar changes in the private sector, has produced a shift in perspective and therefore behavior among health care leaders.

This is a significant point Brill fails to acknowledge — to the great detriment of his thesis. Ironically, though, it's noted toward the end of the book by Gary Gottlieb, the outgoing chief executive of Partners HealthCare in Boston, who says, "There are a lot of problems with Obamacare. But the attention it focused, at least in the industry, on costs with those pilots made a lot of us realize we have to change how we operate."

Change is indeed happening. The results thus far have been astonishing. In 2014, Medicare spending per beneficiary fell, in inflation-adjusted terms. Total Medicare spending was $126 billion, or a whopping 18 percent below what the Congressional Budget Office, in 2009, projected for last year, according to a recent Kaiser Family Foundation analysis. And this Medicare deceleration has substantially affected the long-term Ubudget outlook.