Verdi’s “La Traviata.” Puccini’s “Tosca.” Mozart’s “Le Nozze di Figaro.” What’s wrong with that picture? For most opera lovers, nothing whatsoever. And yet the underlying truth that everyone overlooks is that those works don’t exist without the other major figures attached to the respective works. It should really be Verdi and Piave’s “La Traviata,” for example as the former would {…}