It is true that extraordinarily low long-term bond yields put us outside the range of historical experience. But so would a scenario in which a sudden bond-market crash drags down prices of stocks and housing.
诚然，反常低的债券收益率不符合历史经验。但债券市场突然崩盘拉低股票和房产价格也不符合历史经验。当一个事件从未发生过时，你不可能装出自信的模样预测它发生。