Sometimes I really hate the use of the word "flop." There have been many shows that failed on Broadway, either financially or artistically, that gained a much bigger recognition in subsequent productions over time. I don't necessarily think that a first Broadway production being a "flop" has to mean it's not a good show. I think each show needs to be looked at in its own light, not just dissing it for being a flop.
That said, I loved Caroline from the first time I heard the CD. LOVED it. Never got to see it on Broadway, but did enjoy a wonderful Boston production some years back (and regrettably had to miss another one here a few months ago). I understand why it won't resonate with some people for sure - but the show definitely has its fans. I'm one.