There are plenty of theories about why Joaquin Phoenix was so out of it on Letterman Wednesday night, but the most plausible is that he was just acting. Sure, he may be drugged up, too, but then wouldn't his pal Casey Affleck put down the camera and send the guy to rehab? Affleck has been following Phoenix around filming a documentary (mockumentary?) about him, and the Daily News reports that following his Letterman appearance Phoenix and his crew went to a screening of his movie Two Lovers (where at the very least Gwyneth Paltrow would have attempted to save him with GOOP-isms).

At the screening, "anyone they encountered was asked sign a release form" which stated, in part: “This release is made to allow Flemmy Productions, LLC to include me in the production and/or publication of the documentary project tentatively entitled ‘Untitled Joaquin Phoenix Documentary’ (the ‘Picture’)." The same releases were also handed when Phoenix patronized The Box last week, and likely at that LA appearance in January where he fell off a stage (video!).

If it is some kind of elaborate Kaufman-esque put-on (minus the wit and charm), there had better be an amazing payoff at the end, because at this point the hoax—if it is a hoax—is shaping up like a self-righteous "comment" on how vulgar Americans love a good celebrity flame out. Which of course we do, but who are you to judge, Mr. SpaceCamp? Or as Videogum's Gabe Delahaye put it: "This seems too much like a game being played by a self-indulgent narcissist who doesn't actually understand the rules. Because, obviously: David Letterman: 1. Joaquin Phoenix: 0."