I watched the Cats musical, which I actually had on DVD, a few years ago in anticipation of the fact they were making this movie. I thought it was terrible, strange, and I could not believe it was popular.
I knew the movie was doomed, but had no idea it would be as bad as it ended up being.
I believe the movie Six Degrees of Separation has a joke in it about a movie producer trying to make Cats as a movie and how impossible it would be.