Stimulating reply Jason, thanks. I'll try to address most of your points.

The 'once' is indeed not meant temporally, but thanks for the warning regarding its connotations. It may be that I could have picked a better word.

On the line I'm pushing, Lewis et al may be right that knowing what it is like is identical to ability. However, these kinds of abilities are founded on cognising the quality of phenomenal states, and and retaining this information. The bike rider needs to retain his cognition of the feeling of balance in order to have the ability to ride. So, in this sense, what I later call (perhaps this is loose of me) 'phenomenal knowledge' is basic to the abilities. But 'basic to' 'founded on' and such don't imply that the abilities are distinct from the phenomenal knowledge. I claim that the phenomenal knowledge partially composes the abilities. Any difference between them is just that between parts and wholes. That's why the priority I argue for is not temporal, but yes logical, or perhaps ontological is better.

I don't see that this is embracing the possibility and impossibility of the identity at the same time. This might be a poor analogy, but if so another will do: Sartre says that existence is prior to essence, for man. But that doesn't - it seems to me - imply that essence is separate from existence for us. Rather these are aspects, and this is a logical or ontological issue. Or what about this: triangulairty is prior to having one's angles add up to 180 degrees. Or: the substance of an object is ontologically prior to its propertiedness. And so on. Now it may be that I should have used some such analogies to make my position clearer. Fair enough.

As for your charge that this view is no advance on what Lewis et al anyway propose, I think this is mistaken. I do not concede in the paper that the abilities to recognise etc can be gained without new factual knowledge. What I say is that the appeal to abilities, even if granted, doesn't touch the question of factuality. Lewis et al take the appeal to settle this question. There we differ.

I will, when I get a moment, have a look at your argument, thanks for the link. In the meantime let me know if this answer is any more satisfactory.

Sam