Robert Mugge’s documentary on Katrina’s devastation comes to DVD just in time for the hurricane’s second anniversary and as a film, its strength and weakness is the same thing. Mugge obviously loves the music so he gives Irma Thomas, Eddie Bo, Kermit Ruffins, Theresa Andersson, OffBeat editor Jan Ramsey and countless others plenty of time to tell their stories, show the damage they sustained and to let the world know what happened here. Those stories all take time, though, and Mugge doesn’t hurry any of them along, even when he should. As a result, New Orleans Music in Exile is a little pokey.

Then again, maybe these stories are ones that don’t need to be told quickly, or assembled into a tight, swift narrative. Two years later, it seems valuable to have a document of the destruction partially to recognize how much has changed, and to remind the world just how profound and surreal everything was.

The DVD’s extras add a number of performances including World Leader Pretend performing “A Grammarian Stuck in a Medical Drama” at Voodoo in Memphis. It’s not a song I ever thought about in the context of the hurricane, but its mournful tone (embodied in Matt Martin’s guitar feedback and the sad, wordless chorus) seems very appropriate as a part of the movie’s package. The song ends with Keith Ferguson’s mouth open as if he’s screaming, but the only sound comes from his frantically strummed, heavily distorted guitar. That moment captures perfectly the impossibility of putting the hurricane experience in words, which might be where movies like this come in.