If adding central bank liabilities to the general public debts, a larger CB balance sheet effectively shortens...

If adding central bank liabilities to the general public debts, a larger CB balance sheet effectively shortens duration of the debt portfolio. Hence that portfolio is more susceptible to sudden interest rate hike. A solution to that problem is to create a barbell type of maturity structure by buying up/keeping the medium term bonds on the central bank balance sheet.


https://www.economist.com/blogs/freeexchange/2017/09/unwinding-qe