What we've seen in past recoveries, and coming out of 2008-09 would be the most current example, is that if you withdraw stimulus prematurely the recovery stalls and then you have to put in some new stimulus to get it back. You lose the momentum and you have to restart it. That is certainly a lesson we've all taken to heart.
There are other lessons from history. If you go back to the late sixties and the early seventies, when there wasn't enough attention paid to inflation, the result of that was that we built up a big head of steam on inflation, and then it was very difficult, very costly, to drive that out of the system. I think the lesson from history is that you do want to support the recovery through its full length, and that will require some patience. However, you also need to react to the data as you see it coming in and adjust accordingly so you don't overheat the economy.