I should say at this point that, no, I haven’t turned into a fan of the show itself, the one you can see at your community theater or license for your high school. I don’t believe musicals should need whisker consultants. But as happens occasionally, the right idea can transform the wrong material. If “Cats: The Jellicle Ball” has managed a Grizabella turn, reincarnating itself in fabulousness, do not expect an 18-year run or, pardon me, copycat productions. It’s a lightning strike: not now and forever but now and once.