Hmm, that's very interesting. That sounds imho very similar to what, iirc, Aristotle more or less believed; Plot is character. Forget psychology, forget the insides of their heads, judge them by their actions. For example, if some guy was sleeping in a class room during class, one could assume based off that action, that he has no interest in what the professor has to say. A plot is constructed: he comes, he sleeps. Now, Aristotle would say the next question is not why he sleeps, but what is he going to do next?
I personally, think that type of construction can work quite well in a RP campaign, although it does generally mean a lot of work for the DM ahead of time, unless one is exceedingly good ad libbing stuff and doing it by the seat of one's pants (which I am not!). What do you think Gary? Incidentally, I was not trying to put words into your mouth, so to speak, so no offense intended. Thanks Gary!