My post on models was really a collective reply to comments on one aspect of my original post on PCT. I have been mean ing to post more, but haven't found the time or the inspiration to formulate something substantial yet.

Wait, what? Your two top-level posts weren't about anything specific to human Perceptual Control Theory, just background control theory, and the whole time I didn't really see the point. I was thinking,

"Sure, you can model humans as controllers that receive some reference and track it, just as you can model a human as a set of "if-then" loops, but so what? How would that model do any good compressing our description of how human minds work? By the time you've actually described what reference someone is tracking (or even a sub-reference like "sexiness") and how observations are converted into a format capable of being compared, you've already solved the problem."

I wish I had made the point earlier, but I was waiting for a more explicit application to a problem involving a human, which I assumed you had.