I've understood that it'll be rather extensive documentation of the whole era. Obviously it'll probably cover Sarajevo gig as well, but it was well before recording, let alone release and gigs of the actual Skunworks era. Chris has gathered, with help from the fans, a lot of (album & concert) reviews, articles, fan experiences and whatnot, so to me, it sounds very interesting. It's not like Skunkworks period has been dug deep and covered too extensively in any media before, so I'll gladly welcome whatever anecdotes and stories they want to share of that particular period.
Chris has also, more or less, indicated that Bruce has treated that particular period with bit of sweeping attitude in his book and other sources, which is probably just Bruce's way of doing these things... he prefers to have a good story, rather than doing an extensive fact check. I'm not saying that the upcoming Dale's book will contradict with anything Bruce has said or written, but it's interesting to hear the story of Skunkworks as told by other member(s) of the band.