Bruce Bartlett finds "that only 11 percent of total stimulus outlays definitely added to growth; the rest may have had no effect at all":
I think that much of the criticism of the stimulus legislation on both sides of the political spectrum has been misplaced. Liberals tend to decry the small overall size of the original package, while conservatives say it was too big. But perhaps the very limited allocation for investment and consumption was the problem. Potentially, we could have had a smaller program that was far more concentrated on consumption and investment spending that would have given us more “bang for the buck,” done more to raise growth at a lower budgetary cost, and maybe made both sides happy.
The Dish 