Smash is in previews March 11 at the Imperial Theatre. Megan Hilty as Ivy Lynn, left, and Katharine McPhee as Karen Cartwright. Photo: Will Hart/NBC via Getty Images Rewind to 2012: Glee was one of the most-talked-about shows in America, and scarves were being manipulated in infinite ways. That’s the environment into which Smash debuted on NBC that February. The musical series, about the making of a Marilyn Monroe musical, had a promising pilot and positive reviews, but by April The New Yorker