A Scanner Darkly

Richard Linklater is one of my favorites so when I heard he was making Philip K. Dick's A Scanner Darkley I was pretty excited. This is the story that Charlie Kaufman tried to adapt but gave up on. You might remember in Adaptation when Charlie's brother Donald is writing his script called "The Three". Charlie mentions that nothing is more overused than multiple personalities in hollywood. He also asks Donald how it is possible to film such a script where multiple characters are played by one person (which is of course what Spike Jonze did in that film) to which Donald replies, "trick photography".
Being a big fan of Waking Life, I was also excited to see more use of the animation software that he developed for that project. It seemed like the perfect solution to the Kaufman problem. The film stars Keanu Reeves, Woody Harrelson, Robert Downey Jr., Wynona Rider and takes place in a future where everybody does a drug called Substance B. I was even excited about Linklater's casting seeing how all the stars in the film have had public issues with drugs.
I understand that Linklater was very faithful to the book and even much of the dialogue is included but I couldn't make head or tails of this movie nor could the four other people I watched it with. I really need to see it again but I'm just not sure I want to. In a strange approach, the dual identidy is revealed from the start perhaps to avoid what Kaufman warned about. The problem is that I don't want to be that far ahead of the main character but I also don't want to have some surprise twist a la Fight Club. There are some very amusing scenes of drug induced paranoia in which Robert Downey Jr. and Woody Harrelson steal the show but that's about all I could make sense of or enjoy. I think Kaufman was right to pass on this, maybe there is not way to film it.