Beka, I think it's ignorant to deny shows like The Music Man of the right they deserve of paving the way for many more musicals including RENT. Although it didn't necessarilly change the face of musicals like RENT, it helped to popularize the genre, making way for other shows that would eventually help RENT get to it's feet.
I'm not a fan of CATS because I find it completely not a musical. It's a revue, if anything, and I still don't really consider a revue a musical. I can respect the fact that it brought people to Broadway though.
I sometimes dislike Fiddler because it can be so long and boring sometimes, when it's not done right. I've seen way too many high school and community theatre productions. But it's a monumentally good piece of theatre.
Oklahoma! changed the face of musical theatre, and no one can deny that. It was one of the first musicals where the songs actually progressed the plot, as opposed to stopping the plot entirely for a nice song.
I think all of these hit on the same point: while you might not like them as shows, many can at least respect them for what they've done for musical theatre. And if you can't recognize what they've done for the medium, I suggest you go listen to the cast recording and read the script, because all four of those have had an impact on the art form.
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