Wow. Have you watched "The Defiant Ones" on HBO yet? This is one of the best documentaries of the year. If you want to watch a crash course in documentary-style interview editing, this thing is a masterpiece. My favorite editing trick is when they allow another person's voice-over to play as they show the person they're speaking about's reaction. It seems to fit perfectly with their dialogue. You can tell some of the moments were just bits of time taken between shoots, or reactions to other conversations, or quiet moments, but it creates a really effective tool for adding humor or intensity to the dialogue in a more creative way rather than simply watching a talking head. Really well done all around.
And I have even more respect for my Beats and my much-cooler-than-me mother who gave them to me as a gift a while back.
Anyway, check out The Defiant Ones when you have a chance!