Well, there's also the legality issue, though in the past that hasn't stopped regional/local theatres from making unauthorized changes, but it's harder to do than it used to be.
Broadway productions can often get the kind of support from writers/estates that others can't. But even then, I do agree that changes that are made in the materials don't always work well at all. Trusting that a show will still work as written, without the lure of that big shiny "NEW AND IMPROVED" banner all around it, is often tougher than it should be. |