Comment: Might be because

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In reply to comment: interesting (see in situ)

Might be because

most people either bookmark it for later, since it's a long video, or they're waiting to finish the video before they comment. Either way pretty much guarantees that it'll get bumped off the fast-paced first page.

Different documentary, but this one is pretty good too

http://www.youtube.com/watch?v=UUY9ahSCMG0

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