This movie can only be described as sycophantic. It offers little in the way of a history and is more a collection of sound bites from a scattershot of punk personalities. Unfortunately those who might actually have something interesting to say, such as Ian Mackaye, Henry Rollins, Keith Morris etc. are given the least time. There is also some attention given to the newer pop-punk/emo acts and the debate on whether or not they are punk. I really don't care for any of those bands so I guess it's good the film doesn't delve too deeply into that either.
If you want a good punk documentary check out American Hardcore. If you want a bunch of old farts with blue mohawks reminiscing about the good old days check this one out.