Of all the Grease Live threads trending right now, this is the best one. IMHO
I did Grease for almost four months in dinner theatre. It's how I earned my equity card.
The show we ended up with was a mish-mash of a few different scripts from various productions (namely the OBC and 93/94 revival and the movie.) It was honestly a mess, but a total crowd pleaser.
I always wondered about the legality of what our director did by creating this hybrid. There's been so many revisions over the years.
Basically when you do Grease, people want to see the "movie" onstage but the original show has some differences.
For selfish, nerdy musical theatre reasons, I'd love to see a word-for-word staging of the original script just to see how it would operate.