Five years ago, it seemed that the out-of-town pre-Broadway trial run was dead, the victim of high production costs and increasingly devastating critical reaction. But these days, nearly every big-budget Broadway show is getting a trial run outside the Big Apple, with Chicago having replaced the various Northeastern cities that used to host tryouts. “With a metro area of about 9 million, it has the requisite population base. It has a sophisticated theater audience with a track record of interest in new work. It has an ample supply of technical crew and stagehands who, due to union concessions, come considerably cheaper than their counterparts in New York.”