I was arguing that it is nonsensical to not value utility, as by definition, MPU is what we should be maximizing.

Sorry, I tend to carelessly use the word "utility" to mean "the stuff utilitarians want to maximize," forgetting that many people will read it as "Von Neuman-Morgenstern Utility." You actually aren't the first person on Less Wrong I've done this to.

In fact, in the end, all this boils down to is that you were arguing against utilitarianism, while I was arguing for consequentialism, two very similar ethical systems, but profoundly different.

I agree entirely.