Digging a bit deeper into the balance sheet composition, we find that high-powered money-equivalents, i.e., reserves, are just over $3.1 trillion, while the far more inert reverse repos (which are a byproduct of extremely excessive liquidity creation and/or counterparty and risk avoidance) are a more modest $2.13 trillion...

... with reserves declining by $1 trillion in the past year, as reverse repos actually increased by half that number.

And while one can debate the nuances of an $8.5 trillion Fed balance sheet, or the reserve/reverse ratio relationship until one is blue in the face, one thing is certain: now that the world has been in an "ample reserve" framework since the launch of QE1, there are certain things that are not supposed to happen: one of them is the use of the Fed's emergency USD swap line. If, however, such an instrument is used, as was the case in mid-October, we can immediately deduce that some bank is suffering a crushing USD-funding squeeze (one whose risk is greater than the risk of being slapped with the stigma of using a FX swap). That's precisely what happened with Swiss bank giant Credit Suisse, which we subsequently learned was being crushed by an $88 billion bank run, and only the secret backdoor bailout of the SNB and the Fed kept it solvent (preventing a far greater financial crisis).

Another instrument that should never be used in an ample-reserve world, is the Fed's Discount Window: this "archaic" secured rescue loan arrangement, one in which banks obtain emergency liquidity from the Fed in exchange for loans, is a legacy of the pre-Lehman era, when its mere usage was enough to spark a terminal bank run for any recipient bank. One can argue that the launch of QE was specifically designed to reduce and/or eliminate the use of the discount window by US banks (after all, the post-2009 tidal wave of Fed-created reserves effectively assures that every US financial institution is swimming in money).