Bullard vs. Krugman or the problem with output gaps

"Paul Krugman likes to complain that “freshwater” economists rely on faulty mathematical models as the foundation of their theories. He’s right, they do. And yet his own models are just as faulty. Take his weekend post that argues the Fed should keep rates on hold for “at least two years.” Justifying his argument, he points to his “entirely standard, conventional” economic analysis. (Funny that conventional “freshwater” economics is bunk, but Krugman’s conventional “saltwater” economics is beyond reproach.)"