Obviously, if you aim to lower public debt charges, if you think your base case is a perfect prediction of the future.... Economists including me have never been all that great at predicting the future path of interest rates, so I'm cautious about being too dogmatic on anything I say in this regard.
Again, it plays to the principle that when interest rates are low, and you can lock in some debt at those low rates, that is beneficial for your overall interest charges and what the outlook is for those are going forward.