His comment reminds me of something you said about West Side Story: "If you hire singers who can fulfill the musical requirements of this difficult score, they will probably not be convincing as New York street kids." My friend's thoughts on Audra reflect him feeling the same way about vibrant operatic sopranos on Catfish Row.
I hope that makes it clearer, and I thank you for reading. 😊
(I personally thought Audra was at her absolute best as Bess.)