In the wake of Washington's agreement last month to suspend the debt limit until 2025, Treasury has issued roughly $814 billion in securities on net in order to juice its cash balance. So far, investors have easily digested the first wave of supply, with money-market mutual funds absorbing roughly two thirds of the issuance by yanking $400 billion from the Federal Reserve's overnight reverse repurchase agreement facility.

Combined with the record amount sitting on primary dealers' balance sheets, it's allowed Treasury to sell so much paper without distorting the very front end of the curve.