>Research on morality can tell you a lot about what morals people have, but it can't tell you anything about what morals people ought to have.

Yes, I recommended Haidt because the topic was whether the fundamentalists were acting according to their understanding of morality. If you're saying that research on morality doesn't yield conclusions on something like "real true morality", then I agree. But I'd add that Haidt's research helped me see inconsistencies in my morality, and in this way it's affected my view of the morality I ought to have.

I agree that repugnance can be a good heuristic for personal actions. I wish that people wouldn't impose their sense of repugnance on others, though. You know how Jews aren't allowed to mix dairy products and meat? I thought that was just an arbitrary rule until I went to Israel and talked to some Jews. They didn't just find it immoral because the Torah said so; they found the idea of a cheeseburger or a meat-topped pizza disgusting, as we might find the idea of meat ice cream disgusting. So I'm concerned that repugnance can easily get attached to arbitrary things.

More abstractly, we can view repugnance as nature's buggy hack to get us to avoid harmful things, dating from before we were as intelligent and knowledgeable as we are now. Purity-morality is just harm-morality implemented on an obsolete system. Now that we're intelligent enough to judge harm more competently than instinct (i.e. we get fewer false positives), we can and should override that judgment, when it helps us. (Trivial but real example from real life: I used to find mushrooms disgusting, just because. After Haidt got me thinking about the usefulness of repugnance, I looked up the nutritional value of mushrooms, found that mushroom-phobia was unhelpful, and decided to get over it.)

Hubris!