Don’t deal "magic", only dish "dirt". To presuppose that: "If the Fed can cause a 500 basis point change in interest rates, it is absurd to wonder if monetary policy is important", when said modeling is magic, is disingenuous, and not dirt. RoC's in money flows, volume X's velocity = RoC's in P*T (where N-gDp is a subset). But we are not done. The distributed lag effect of money flows, both the proxy for real-output, and the proxy for inflation, have been mathematical constants for > 100 years. Ergo, then you will know, in advance, whether *real* (& nominal) rates will increase and vice versa.