The excitement is real, but the way the buying is structured does little for mortgage rates. When the Fed reinvests the proceeds from its maturing mortgage-backed securities, the question is where those dollars go. Directing them into short-term Treasury bills is very different from buying longer-duration bonds. The disconnect is location on the yield curve. Treasury bills sit at the short end, and mortgage rates take their cue from the intermediate-to-long end, roughly the 7-to-10-year part of the curve. Buying bills adds demand where mortgages do not live. The effect is a steeper curve (short end down, long end roughly unchanged) rather than downward pressure on the yields that actually set your mortgage rate. That is why a move some hoped would be a tailwind for mortgage rates amounts to close to a non-event for them. The broader takeaway: winding down tightening can help sentiment at the margin, but composition matters more than the headline. To move mortgage rates, the buying would need to go into longer-duration Treasuries or into mortgage-backed securities themselves. Watch what the Fed reinvests into, and as always, none of this lets anyone promise a direction for rates.