Just a quick shot. One growing point of tension that I that has both semantic and substantive difficulties is whether or not we regard the situation in the mortgage markets as “structural.”
Clearly the health of the mortgage market is strongly influenced both the business cycle and likely by monetary accommodation directly. It also is dynamic in that we don’t expect things to last.
At the same time its also clear that it changes how monetary policy affects the economy. To illustrate, the problems in the mortgage market are well known but look at commercial banking outside of the mortgage market.
A rapid return not just to normalization but to conditions that are almost as good as it gets.