Is Johann David Heinichen’s Flavio Crispo one of the greatest operas never performed? Well, at least until this world premiere performance in 2015 (some 300 years after the fact). It has everything going for it: brilliant writing for voices and instruments, novel orchestration, and the obligatory silly plot. And yet in an intrigue worthy of an opera, the two lead castrati – Senesino and Berselli – ganged up on Heinichen during rehearsals, accusing him of sloppy word-setting. It was apparently only in jest, but Heinichen’s employer...