Very interesting! While highly praised, I've always felt this is one of the most overlooked aspects of MJs career in terms of material available (but I heard somewhere that OTW 30 didnt materialise because there simply isn't enough bonus material from that era anyway)... but who knows! I'm very excited to see some new studio footage! Hopefully Lee pays more attention to the creative aspects of MJ and the creation process of OTW. I felt Bad 25 focused a bit too much on the cultural impact of Bad and while that's important, I feel it's as equally important to focus on MJ as an artist.
Everyone knows of the cultural impact MJ had (especially in the 80s), but not enough people know him as an artist unfortunately.
If they've actually worked on an MJ project or have been heavily inspired by MJ and are knowledgeable about him, I don't mind having them in the doco. If anything, it draws their fans to at least look up the documentary (and who knows, maybe we'll get some new MJ fans!)
Like I didn't mind Kanye being in the doco. He made some interesting (and true) points about MJs career, how the Thriller era was more iconic but the Bad era was more influential etc. I haven't a clue as to why Bieber was there. Yeah, he's influenced by MJ but I don't really see how him talking about how he does the anti-gravity lean when his planes take off has much relevance... at least Kanye worked with/on an MJ project and brought interesting thoughts to the table.
I don't mind VHS clips either, just so long as they're extra sure there is no better quality source available. I'd rather have VHS quality video than none.