The NYT article says precisely that recessions happened 6 months to 2 years later in all cases, except in one case where the economy dipped but wasn't officially a recession in the 1960s. This is different than a stopped clock that is eventually right. In the last 50 years we had recessions or at best a very poor economy with almost no growth (only one time avoided a recession by defn) with 6-24 month lead time after negative yield curve.