As many have said, these cast changes are mind boggling. It would have been one thing if it were say Murphy who was filling in for all of those performances (a super strong and capable principal), but even for her that kind of work load is dangerous. I can't imagine Seo handling all of that, and without getting injured. Does McKenzie think if he works her like a dog, she'll finally get stronger? Or does he see no fault with her and thinks we all feel the same? It's a terrible shame that a few soloists (and even Boylston) aren't given some of these opportunities. I'm just glad I haven't bought any tickets yet....