The orchestra was not live. It was pre-recorded. I was at the rehearsal this morning. He got it right then, but there was a sound problem with his very last note.
What happened was Howard kept singing and forgot the song cut to a new section. It was his fault, but understandable. After singing the role for thousands of performances and many years, the guy must be like a robot.
"The Spectacle has, indeed, an emotional attraction of its own, but, of all the parts, it is the least artistic, and connected least with the art of poetry. For the power of Tragedy, we may be sure, is felt even apart from representation and actors. Besides, the production of spectacular effects depends more on the art of the stage machinist than on that of the poet."
--Aristotle