I'm sorry to pick on Steve so much lately, but this whole thing really is beyond silly...
...apparently now uber-Keynesian Paul Krugman agrees that weak investment is the primary signature of the business cycle!!!!
This is why you should read Facts and Other Stubborn Things. I'm an amateur, I know. I'm not one of the big-name guys. But I'm not regurgitating total nonsense either. A couple days ago you had a set of people telling you Keynesians think it's all about consumption and that Bob Higgs did this great service by pointing out that investment is weak. I said early on that everyone knows investment is the most volatile - you can't really call yourself an economist if you don't know that. I said Keynesians are of this opinion too (indeed - regular readers know I've been saying Keynesianism isn't consumptionism for a long time).
And since that time, who have we had come out and agree with me:
Greg Mankiw (big shot Keynesian)
Paul Krugman (big shot Keynesian)
John Maynard Keynes (interpreted by Barro, Mankiw, and Krugman who all say he thinks this)
Karl Smith (medium shot Keynesian)
Me (small time Keynesian)
Do we have any Keynesians challenging this idea? Not that I have seen. This is like the 1920-1921 paper all over again. Lots of insistence that Daniel Kuehn is putting a rosy face on the dumb Keynesians, or that Daniel Kuehn may have gotten Keynes right, but modern Keynesians wrong, followed by several big-name Keynesians coming out and saying exactly what Daniel Kuehn said.
Here's a suggestion to the blogosphere: human beings are intelligent. If you come across what you think is an easy to articulate ace-in-the-hole argument based on readily available data that you think completely refutes a long-standing theory that an intelligent person adheres to, you're probably misunderstanding the theory. There's no such thing as a $20 bill lying on a sidewalk. There's no such thing as a free lunch. Intelligent people recognize obvious things like the volatility of investment, the heterogeneity of capital, and the fact that government spending isn't a panacea. Theories that don't recognize these things don't survive for 70 years.