
In Jeon and Vernengo (2008) we suggest that labor productivity is endogenous, explained essentially by the expansion of demand, and old idea, implicit in Adam Smith's vent for surplus, and part of a well established empirical regularity, the so-called Kaldor-Verdoorn Law. In other words, it is the weak recovery, caused by a contractionary fiscal stance, and the slow pace of private spending growth as employment increases, that explains the poor performance of productivity. In this sense, the causes are considerably simpler, connected to macro policy, rather than the long-term pessimism of Gordon and Summers, which now talk about secular stagnation (see also this book).
Perhaps the more interesting stuff in Blinder's piece is his discussion of what the 'serious people' in the mainstream consider the natural rate to be. He says:
"the 'central tendencies' in the Federal Open Market Committee’s latest published forecasts range from 5.2% to 5.5% for the 'full-employment' unemployment rate, and from 2% to 2.3% for the potential GDP trend."Note that Blinder also thought that the speed limit was around 2% back in the late 1990s (here his debate with Bluestone and Harrison). And yes he is a Keynesian (a New Keynesian). With friends like this...