After a decade of zero rates and QE post-2008, the financial system can no longer function without continuous stimulus. Attempts to tighten policy, as seen with the 2018 repo crisis, immediately cause breakdowns, forcing central banks to reverse course and indicating a permanent state of intervention.

The Fed's SRF is proving ineffective at capping repo rates. Despite rates trading well above the facility's level, usage was minimal. This indicates a market stigma or hesitation, questioning its ability to function as a reliable backstop for temporary liquidity shortages and control rates.

The common narrative of the Federal Reserve implementing Quantitative Tightening (QT) is misleading. The US has actually been injecting liquidity through less obvious channels. The real tightening may only be starting now as these methods are exhausted, signaling a significant, under-the-radar policy shift.

The Fed has a clear hierarchy for managing liquidity post-QT. It will first adjust administered rates like the Standing Repo Facility (SRF) rate and use temporary open market operations (TOMOs) for short-term needs. Direct T-bill purchases are a more distant tool, reserved for 2026, as the system is not yet at 'reserve scarcity'.

The impending halt of the Fed's balance sheet reduction (QT) is not a reaction to a major economic crisis, but a technical necessity to prevent stress in short-term funding markets as bank reserves become scarce. The Fed is preemptively avoiding a 2019-style repo spike, signaling a quiet return to mild balance sheet expansion.

Contrary to the push for an "efficient" (smaller) Fed balance sheet, an abundance of reserves increases bank safety. Bank reserves are immediately accessible liquidity, unlike Treasuries which must be sold or repoed in a crisis. This inherent buffer can make the banking system more resilient.

The Fed's decision to end quantitative tightening (QT) in December, not immediately, could strain funding markets. Investors should monitor rising overnight repo usage and widening SOFR-Fed funds spreads as key indicators of impending weakness in speculative equities.

Unlike September 2019, the recent corporate tax day saw no funding crisis. The mere existence of the Fed's Standing Repo Facility (SRF) calmed markets, preventing panic. This psychological backstop, combined with higher bank reserves and a better regulatory environment, proved crucial for stability.

Recent spikes in repo rates show funding markets are now highly sensitive to new collateral. The dwindling overnight Reverse Repo (RRP) facility, once a key buffer, is no longer absorbing shocks, indicating liquidity has tightened significantly and Quantitative Tightening (QT) has reached its practical limit.