Robert Gottleib is feeling weary of New York City Ballet’s Balanchine tribute. “There’s been so much spin and so much P.R. that it’s hard to remember just what it is we’re celebrating. But once you’ve blown out the party candles, what do you have? More of the recent unpredictable, uneven level of performance that was unthinkable during the 35 years when Balanchine commanded the company.”