I think any functionalist definition for the intensity of either would have to be asymmetric, at least insofar as intense pleasures (e.g. drug highs or euphoria associated with temporal lobe epilepsy) are associated with extreme contentedness rather than desperation for it to continue. Similarly-intense pains, on the other hand, do create a strong urgency for it to stop. This particular asymmetry seems present in the definitions you linked, so I’m a little sceptical of the claim that “super-pleasure” would necessitate an urgency for it to continue.
I’m not sure whether these kinds of functional asymmetries give much evidence one way or the other—it seems like it could skew positive just as much as negative. I agree that our understanding might very well be human-relative; I think that the cognitive disruptiveness of pain could be explained by the wider activation of networks across the brain compared to pleasure, for instance. I think a pleasure of the sort that activates a similar breadth of networks would feel qualitatively different, and that experiencing such a pleasure might change our views here.
I’m interested in arguments surrounding energy-efficiency (and maximum intensity, if they’re not the same thing) of pain and pleasure. I’m looking for any considerations or links regarding (1) the suitability of “H=D” (equal efficiency and possibly intensity) as a prior; (2) whether, given this prior, we have good a posteriori reasons to expect a skew in either the positive or negative direction; and (3) the conceivability of modifying human minds’ faculties to experience “super-bliss” commensurate with the badness of the worst-possible outcome, such that the possible intensities of human experience hinge on these considerations.
Picturing extreme torture—or even reading accounts of much less extreme suffering—pushes me towards suffering-focused ethics. But I don’t hold a particularly strong normative intuition here and I feel that it stems primarily from the differences in perceived intensities, which of course I have to be careful with.
Stuff I’ve read so far:
Are pain and pleasure equally energy-efficient?
Simon Knutsson’s reply
Hedonic Asymmetries