Discretion rather than rules: Equilibrium uniqueness and forward guidance with inconsistent optimal plans

New Keynesian economies with active interest rate rules gain equilibrium determinacy from the central bank's incredible off-equilibrium-path promises (Cochrane, 2011). We suppose instead that the central bank sets interest rate paths and occasionally has the discretion to change them. With empirically-reasonable frequencies of central bank reoptimization, the monetary policy game has a unique symmetric Markov-perfect equilibrium wherein forward guidance influences current outcomes without displaying a forward guidance puzzle.