They won't do that. If Idina goes on tomorrow, she will do the role on her own, or not at all. If she does go on, she may have to take it easy and not fly (if the producers will allow this).
"Maybe Idina Could be Nessa tomorrow"
Oh. My. God. What a cute thing to say! ::rolls eyes::
"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