Having gone through a pretty good Econ PhD program fairly recently, I can tell you that the mainstream of the profession has an unbelievably facile understanding of business cycles. This is still the area where the Austrians soar above their colleagues.

Does Debt Make Capitalism Financially Unstable? By Frank Shostak "The Post-Keynesian School of Economics claims that business and personal debt create instability that sinks the U.S. economy. Private debt, however, is not the cause of boom-and-bust cycles."