Therefore, this blog post seems spot-on to me. He's responding to a guy (Ostler) who is trying to prove that morality in Mormonism has a strong theoretical foundation, just like religions which believe in creation ex nihilo. The writer observes that the theoretical argument is complicated and uncompelling, and maybe even superfluous.
Happiness isn't something God, from outside of the situation of love, bestows on those who love; happiness is something internal to love itself. It's, in Ostler's appropriate word, a byproduct of love.
I couldn't agree more about all this. My question, then, is simply: Why not begin and end here? Why bother with Kant? I suspect that Ostler's reason is that byproducts aren't enough to ground moral obligation. How can one claim to have a moral obligation to love if one's simply after love's associated affects? (As a byproduct and not simply a product, it might be said that happiness can't be called love's teleology, and so obligation doesn't return in the form of a consequentialist ethics here.) And I think Ostler would be right to point out this problem, were he—as I suspect he would—to do so. But then my question would become: What's so important about moral obligation? Is it so necessary for Mormonism to have a theory of moral obligation? Why can't we say simply that God reveals to us the happy way to live? Why do we need to say that God reveals to us the happy way to live toward which we have an obligation?
All of this is to ask, in the end, why we can't simply agree with the several individuals Ostler refers to at the beginning of the chapter. Why not just confess that Mormonism can't, given its ontological commitments, produce a satisfactory theory of moral obligation? Why not argue that that incapability is one of Mormonism's strengths? Why not agree with the so-called critics that Mormonism is more like training in the good life than exposition of universal moral obligation?