If it's a no-brainer that bonds should sell off as Fed unwinds, and if there's no such thing as a free lunch, then bonds ought not to be sold.
If Fed hikes then emerging markets take a hit. If emerging markets take a hit, there will be a flight to safety. If there's a flight to safety, then Treasuries get bid up. If Treasuries get bid up, the price of bonds gets bid up. If the price of bonds get bid up while Fed is unwinding balance sheet, then the unwinding will be successful. If Fed unwinding is successful, there's really nothing to be bearish about aside from over-stretched valuations and the economic cycle.
Bottom line: if bonds rally while Fed unwinds, then the Fed's operation will be successful.
