If you’re tired of Sumner (how would that even be possible?) and you suspect Krugman is blowing smoke (totally possible), then read this Altig post about the problems with modern macro (which he calls New Keynesian hence Krugman’s smoke).
Altig works for the Fed so he’s tainted, of course, because “real criticism of the central bank has become a career liability”. Real criticism like this and this and this got those guys fired! Oh wait.
(Seriously, read the Sumner piece, too. It compliments the Altig’s piece in a combination that’s a way more serious critique of macro than Krugman’s.)