1. His model was considerably more highly aggregated than that of, say, Lawrence Klein's "Old Keynesian" models.
2. The guy seems to agree that one difference between Austrians and "Anglo-Americans" is that Austrians do not think consumption and investment demand move in the same direction over the business cycle. Mises disagreed with this. I know a lot of modern Austrians will foam at the mouth if you suggest this. But I don't think many people appreciate that Hayek thought this (at least as of 1941). They find it much easier to accuse their accusers of being idiots.