The Fed holds interest rates to be its primary control valve, with lower ones providing a stimulus to the GDP and higher ones a brake. Self- evidently, therefore, interest rates below the inflation level are a stimulus because they amount to economic subsidization of debt, and the spending or investment which results.
Still, even the primitive Phillips Curve theory of the growth/inflation trade-offs screams out that the Fed is way behind the curve, even based on its own defective economic models. After all, why in the world has it permitted its ultimate control valve and benchmark—the 10-year UST—to carry a negative real yield for 36 of the last 38 months.