Operatic performances in movie theaters are mushrooming, not only in the United States but overseas. British musical gadfly Norman Lebrecht takes a look at the phenomenon and — as you might expect — sees some problems with it. On this side of the ocean, the Metropolitan Opera, which started it all, has two more live broadcasts coming up soon: Peter Grimes on March 15 and Tristan und Isolde a week later. La Bohème and The Daughter of the Regiment will conclude the season in April.