Testing hypotheses derived from or inspired by IIT will probably be on a case-by-case basis. But given some of the empirical work on coma patients IIT has made possible. I think it may be stretching things to critique IIT as wholly reliant on circular reasoning.

That said, yes there are deep methodological challenges with qualia that any approach will need to overcome. I do see your objection quite clearly- I'm confident that I address this in my research (as any meaningful research on this must do) but I don't expect you to take my word for it. The position that I'm defending here is simply that progress in valence research will have relevance to FAI research.

Out of curiosity, do you think valence has a large or small kolgoromov complexity?