The Governor of the Bank of New Zealand operates under such a performance contract; he can be removed from office for failure to achieve his inflation target. I have never found the literature on time inconsistency particularly relevant to central banks. Surely central banks realise they are facing a repeated game, not a one-time game.
The revisions in expectations were fueled by the Fed’s forward guidance referenced to inflation and unemployment, official statements suggesting the proximity of tapering, and incoming data revealing improved economic conditions and prospects in the United States.