I'm not sure it's important that my conclusions be "interesting". The point was that we needed a guideline (or set thereof), and as far as I know this need has not been previously met.

Once we agree on a set of guidelines, then I can go on to show examples of rational moral decisions -- or possibly not, in which case I update my understanding of reality.

Re ethical vs. other kinds: I'm inclined to agree. I was answering an argument that there is no such thing as a rational moral decision. Jack drew this distinction, not me. Yes, I took way too long coming around to the conclusion that there is no distinction, and I left too much of the detritus of my thinking process lying around in the final essay...

...but on the other hand, it seemed perhaps a little necessary to show a bit of my work, since I was basically coming around to saying "no, you're wrong".

If what you're saying is that there should have been no point of contention, then I agree with that too.

"How can a terminal value be rational?": As far as this argument goes, I assert no such thing. I'm not clear on how that question is important for supporting the point I was trying to make in that argument, much less this one.

I have another argument for the idea that it's not rational to argue on the basis of a terminal value which is not at least partly shared by your audience -- and that if your audience is potentially "all humanity", then your terminal value should probably be something approaching "the common good of all humanity". But that's not a part of this argument.

I could write a post on that too, but I think I need to establish the validity of this point (i.e. how to spot the loonie) first, because that point (rationality of terminal values) builds on this one.