I'm sympathetic to much of what you say here, and probably agree with it as a first approximation. But I dislike the implication (not sure whether intended or not) that a single way of making decisions (calculation vs. something closer to our intuitive decision procedure) is right in general. It seems far more likely to me that there are situations where one or the other, or some combination of procedures, is likely to be most useful; and the interesting questions are about what to use when, rather than what to use always and everywhere.