Steelmanning is making the best possible argument for a position, whereas CEV is sorting out all the delusions and contradictions in someone's thinking and giving them what they would want if they were wise enough to know it. Central bankers engage in extrapolated volition when they try to make the economy run in a way that will make people happy, even if what they do is not what the woman on the street wants them to do because the woman on the street has no idea how the economy works. Friends engage in extrapolated volition when they intervene in a marriage or a drinking bout and say "you are ruining your life, and we are stopping it now." Extrapolated volition is paternalistic ("you think you want that, but I know better ...") and Yudkowsky's CEV would demand God the Father. Yud's original paper is available.