I think the real 'point' of this documentary, at least for me, is a look into the world of standup comedians, with a wide range of talent interviewed from the nearly-fossilized to the still-headlining. The film is also a kind of study into what makes us laugh -- sometimes despite ourselves.
It made me reflect on how standup is often a competitive, lonely business-- certainly compared to theater and improv. I saw it on vacation in L.A., and I'm sort of glad I got to see it in a forum with other people, because gauging the reactions of the room was part of the experiment, I thought. Watching it alone on DVD would have done little for me.
The filmmakers must have decided that single-shot talking head interview segments would be too uninteresting, because they kept showing scenes of two-camera interviews, at approximately right angles, editing back and forth between, say, the left side of Paul Reiser's face and his right. This got annoying to me as a matter of technique.
If you're not a fan of a lot of old comics, or interested in exploring the line between humor and disgust, this one is not for you. Not a great film, but I can understand the sensation over it.