There is a remarkably regular pattern between the Fed Funds rate and Commercial & Industrial Loans as a proportion of total bank credit:
Recovery in C&I Loans has always coincided with recovery in the effective Fed Funds rate. In fact, the Fed Funds rate tends to precede C&I Loans, slightly. So, this recovery is unique.
Corporate spreads are still a half point higher than typical recovery lows, and banks don't seem to be excessively profitable. There are plenty of reasons why rates would still be low. And, the natural short term rate was probably significantly below the zero lower bound, so there was no way to measure a recovery in short term rates. And, the banks were so hobbled, this might be a recovery that is unusually supply based, whereas previous recoveries were generally demand based.
But, this does make me wonder about the shape of interest rate movements to come. I wonder if demand for C&I Loans will be fairly inelastic even if rates go up a couple percent. If the limit to bank asset growth has been the product of some discrete risk management, capital, or regulatory limits instead of some continuous function of supply and demand of credit, maybe rates are well below their functional equilibrium levels, but it just hasn't made much difference in credit markets because of other factors.