Earlier in the evening, Benjamin Millepied's pas de deux, Triple Duet, was less successful. It was a pleasant enough piece, to a Bach partita, but there was not enough cake under the icing. It suffered hugely, too, in being programmed back to back with Balanchine's Duo Concertant, a pas de deux choreographed 30 years ago, and looking as thrilling today as if it were its premiére.