You are right about yields being below the historical norm. And, taken just by itself without consideration for the future, keeping the bond buying program in place would help the economy in the short run.
With that said, their will be a consequence down the road to all those bonds they hold and the more they hold/accumulate, the worse the future consequences will be. There is no free lunch.
I don't think we are going to have a thriving economy again until we try to rebuild our manufacturing base and provide more liveable wage jobs. JMHO.
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