--but there would no longer be a target on inflation or real GDP. It would be the sum of the two.
In a world of full employment targeting, as full employment.... And Mario suggests quite rightly that in fact our measures of full employment or NAIRU move over time. Of course they move over time. All kinds of real variables move over time in response to changes in labour market policies, productivity growth, technological change, etc.
As those things change over time, does that mean we're going to have a shifting target from the central bank? That mobility in such a target, if that happened, would be not a simple thing to communicate. To me, the big advantage.... I mean, if you buy the argument that anchoring expectations is important, then it's only a hop, skip, and a jump to buying the idea that inflation targeting is also very valuable, because it has those simple communications.