At the time that “considerable period” was introduced, the market was pricing in a significant degree of near-term policy tightening, presumably on the expectation that the sharp pickup in growth in the third quarter of 2003 would induce the FOMC to raise rates.
However, this market reaction placed insufficient weight, I believe, on the fact that the expansion that began in mid-2003 was characterized by exceptional gains in labor productivity, which implied in turn that the rapid growth in output did not materially increase the pressure on resources.