Take the touring company of An American in Paris: “In between big song-and-dance numbers like ‘Fidgety Feet,’ ‘But Not for Me’ and ‘I’ll Build a Stairway to Paradise,’ the musicians checked their phones, perused a paperback or prepped their instruments until their next cue to play. As the show moved toward its finale, I appreciated that if I was going to spend the evening perched in proximity to a piano, I couldn’t ask for anything more than for the pianist to be playing Gershwin.”