Normative uncertainty does not seem particularly interesting. You can just use set multiplication over probable futures and evaluations of them, and wind up with a regular problem with certain evaluations. It even agrees with normal methods if you assume a single, certain evaluation.

Now, as a concept it's important - realizing that you might not know what you want is a tremendous source of uncertainty that is easy to overlook. I just don't think that any new concepts or mathematical tools are needed to tackle it.