It is rather well accepted that transparency is preferred for policy, because it anchors better expectations, people generally do not like uncertainty, and discretion can lead to adverse biases compared to set policy rules. Yet, the United States exhibit little transparancy, with the Federal Reserve being one of the few western central banks not to declare some explicit policy target, and fiscal policy being as uncertain as ever. That would not be a big deal if the welfare costs were low, but you can think that there are high and in the case of fiscal policy are currenctly holding back the recovery.
Giorgio Di Giorgio and Guido Traficante are taking a closer look at the welfare benefits of inflation targeting. For this they use a model where households observe policy interest rates and do not know whether their changes are due to reactions to output gaps or shocks to the inflation target. Households are sophisticated, they use a signal extraction device to estimate the latent, unobservable variable. Yet, they still face substantial costs from the uncertainty. Money is not neutral because of Rotemberg pricing, a variant of Calvo pricing. Oh well, I guess this is what you need to do to get a result with some bite.
Households know there is a policy rule that determines the interest rate from the output gap (unobservable) and the inflation target (stochastic and persistent) as well as known preference and cost-push shocks. In other words, households know a lot about the structure of the economy and the shocks, except for the policy shock, but then somehow cannot figure out what the output gap is. The central bank can, though, but then has for obscure reasons a trembling hand when it comes to set its inflation target. That seems to be quite the opposite of what I would have thought: everyone is confused about the output gap, and only the central bank knows what the inflation target is. Instead of a story of households trying to disentangle output gap and inflation target from the interest rate signal, one would have a story of a central banker not quite sure what to do given the circumstances. Too bad, this could have been an interesting paper.