Lately, I’ve been pondering how marvelous and challenging live and in-person human performance can be. Of course, machines perform as well, by design. But machines don’t have feelings and/or unique intelligence that can be mobilized to enhance expression. We also may enjoy products that convey or reflect on expression, such as films, recordings, books and magazines.

But nothing can be as marvelous as live human expression offered up to others.

A week ago, while in New York City, I attended a new Broadway musical, “Kimberley Akimbo,” a family comedy about a group of teenagers. Accomp...