I believe you are referring to the David L. Burge perfect pitch course. He does relate perceiving tones to perceiving colors, but it isn't done through association. The "pitch color" is simply the quality unique to a particular tone that allows someone to identify it. This unique quality that distinguishes pitches in the realm of sound is very similar to the quality that distinguishes different light frequencies in the visual realm. I have been doing the exercises he suggests for several years now, after getting his 1.0 course from the library (there is now a 2.0 course which I don't know much about. If you want an advertisement and ordering information, go to www.eartraining.com ) At first I wasn't sure if I was hearing the pitch colors at all, but now I am quite confident. I feel a greater understanding of music with perfect pitch ability than I had before. I have used Personal Genius, Belief, New Behaviour Generator, Automatic Pilot, and Memory Supercharger with goals of usually "more clearly hearing pitch colors in all situations", and also Perfect Health, which has a part about halfway through about comparing being a health tuner with a tuner with perfect pitch. With New Behaviour Generator, I simply modeled someone with perfect pitch.
My sticktoitiveness with doing the exercises every day was most dramatically improved by the visualization procedure meant to help one stick to the Photoreading system(which I also found at the library) that was on one of the Photoreading course tapes (one of the last ones). After doing that it was smooth sailing, it still is, I suppose, as perfect pitch development is more of a journey than a destination.
Developing perfect pitch has completely changed my outlook on life, in fact. I am more perceptive now, less judgemental about my perceptions. I'm more of an observer now. I had to change this to be able to hear the colors of the tones as I now can. This is what brought my interest to things like Photoreading which I probably wouldn't have considered before, but now that I developed ability to hear pitch colors, I feel like anything is possible and I have a better grasp on how it's possible.