What you propose is possible, but much more money could be made by creating the software, creating the database of edits and selling the database to users, to let them view or create a copy for themselves.
I expect such technology to be built into DVD players before long. You'd sign up for a service, download data for movies you wanted to butcher up, and everything would be automatic after that. Easy enough to create, certainly, and you'd be able to license the software to the DVD makers.
Oh, wait....betcha Sony is already working on such a thing in-house, so it's likely that all of our budding entrepreneur's efforts would go to waste.
If it's a good enough idea, it's already in the works, I'd think.
Sure, but again the discussion was just the legality. Somebody asked if it would be legal and I said "yes if...", that's all I was discussing. I'm not even interested in such a service as a customer, both my parents were Marines, there's very little language Hollywood can present that bothers me, and if there's something else in a movie that bothers me I just don't want to see it, not interested in a scrubbed version. Actually there was at least one company last year that was marketing a thing for use with high end DVD players that would skip offending chapters and mute offending dialog on the fly. As DVD players get more controllable that will probably expand.