To watch Larry David make his Broadway début, in his self-penned "Fish in the Dark" (at the Cort), in the same week that Helen Mirren stars as Queen Elizabeth II, in Peter Morgan's "The Audience" (at the Gerald Schoenfeld), is to learn something about the benefits and the limitations of shtick. Derived from the Yiddish word shtik, meaning "an act" or "a gimmick" (from the German Stück, for "piece"), it can also ref…
