I think he wants a system which works like realism, in that there are definite answers to ethical questions ("fixed", "frozen") ,but without spookiness.

Yudkowsky,'s theory entails the same problem as relativism: if morality is whatever people value, and if what people happen to value is intuitively immoral , slavery, torture,whatever, then there's no fixed standard of morality. The label "moral" has been placed on a moving target. (Standard relativism usually has this problem synchronously , ie different communities are said to have different but equally valid moralities at the same time, but it makes little difference if you are asserting that the global community has different but equally valid moralities at different times)

You can avoid the problems of relativism by setting up an external standard, and there are many theories of that type, but they tend to have the problem that the external standard is not naturalistic....God's commands, the Form of the good, and so on. I think Yudkowsky wants a theory that is non arbitrary and also naturalistic. I don't think he arrives a single theory that does both. If the Moral Equation is just a label for human intuition, then it ssuffers from all the vagaries of labeling values as moral, the original theory. If the Moral Equation is something ideal and abstract, why can't aliens partake?