"Back in Time" seems to proceed from the best of intentions, and I kinda feel bad for expressing any disappointment. There's certainly a lot of material crammed into this thing, but the movie-intensive stuff seems to be at odds with the fan adulation. I approached this as a fan, so I'd heard the commentaries, read the book, heard Bob Gale tell the same making-of story a hundred times, so a great deal of this doc was a retread. Nobody's fault, but it did seem to tease a behind-the-scenes angle that never really materialized.
On the plus side (and this is primarily if you're fairly new to "Back to the Future"), like I said, there's a lot of stuff here. Michael J. Fox had some good anecdotes, the restoration of the A-car was kinda cool, as well as the Secret Cinema portion. And some of the fan-based material is genuinely touching, particularly the cerebral palsy guy and the cancer survivor.
But really, this is for the general fan, and there's nothing wrong with that. Have at it.
6/10