From his post this weekend:
I take an outlier point of view, which is that the Fed is not important for the macro economy. Walrasian economists needed something to pin down the nominal price level, so they nominated the money supply. I instead take the view that money and inflation are largely social conventions. Extreme measures by the government can change these social conventions. Otherwise, in my view, the belief in the power of the Fed is a superstition. This superstition is best maintained if the Fed’s actions are mysterious. If the Fed were to follow a transparent rule, I think that the superstition would be exposed for what it is.
This is at the bottom of his take on the Neo-Fisherite (keeping rates low encourages low inflation) & market monetarist (target nominal market levels) thinking.