I watched that Boston Pops broadcast back in the day. There was another song they did together, something more up, forget what it was. They were trading fours and Wynton tried to get "modern" by playing some quartal or chromatic thing, you know, HIPMODERN and Sarah just sang it back to him, with elaboration and without missing a beat or batting an eye.
So when Betty Carter handed Branford his ass back to him on the Night Music show that one time, I was like, wow, these kids don't learn, do the... LOL.