Ezra is generous, to my mind:
What you can say about an annual slowdown of 1.5 percentage points is that it would be a magnificent achievement given the political difficulties of health reform, but it's quite a bit lower than could be achieved absent those constraints. [...] But though it's true that this new definition of success is ambitious given what we're likely to achieve amid a broken political system and a powerful health-care industry, it's probably quite modest given what could be achieved in more straightforward circumstances. And that's worth keeping in mind.
The kicker, though, is that 1.5 percentage points happens to be exactly the goal that the healthcare industry voluntarily offered for itself.
This puts me very much in mind of Susan Greenhalgh's Just One Child, which examines the conception, development, and implementation of China's one-child policy from the framework of an anthropology of policymaking. It's a fascinating read and I highly recommend it. In it, she notes that a particular goal--constraining the population at 1.1 billion--was arrived at by a particular set of policymakers based on computer models designed for missile control that were not equipped to consider concerns that social scientists would have thought paramount: demographics, the varying economic needs of rural vs. urban families, etc. This goal, enshrined in a highly technical report that won definitive status almost immediately due to very impressive and impenetrable math, political connections, and the privileging of "hard" science over social science under Mao, quickly became the unquestioned aim of population control policy in the Deng government, despite protest from social scientists that the goal was too ambitious and would harm rural families as well as women. (1.1 billion advocates retorted that it was better to aim too high, in case of falling short.) The result was the often punishing policy we know today.
I should hope the analogy is fairly obvious. In both cases a numerical policy goal was nominated based not on the most rigorous, inclusive, and pragmatic analysis possible, but rather based on other considerations and due to disproportionate political influence. It seems the target of 1.5 percentage points is well on its way to becoming an authorless, Reasonable number that everyone will endorse. The healthcare industry will be pleased, healthcare reformers farther from the centers of power--but often with better information about the effects of policy on the ground--will protest to little avail, and soon we shall have the healthcare policy that became inevitable when this number became The Number.
Policymaking is tricky business, and it has a tendency to turn into a sort of Rube Goldberg Machine (see below) where the final effect seems to have almost nothing to do with the original force even though the chain of cause and effect is there; it's just wended its way through a dizzying array of objects, people, offices, departments, obstacles and pathways.
Best Rube Goldberg Ever - Watch more Funny Videos
The final policy outcome of lowering costs by 1.5 percentage points (assuming policy is effective) will probably seem to have nothing to do with the industry by the time it is realized, or if it does this will be only because they, as Knowledgeable Businessmen with Experience, were wise.
However, that the number came from the healthcare industry is, as Ezra says, worth remembering.
Update: Also see DDay on the way healthcare can die.