I am not saying that some people haven't used 10w-30 and believe their transmission works better. I was simply pointing out to the OP, who is having shifting problems if you'll recall, that he is using non-spec oil.
I posted the factory service manual. All you've posted is other people's opinions. Sorry, but a contrary opinion, even by a Jeep engineer, does not outweigh the official service publication and you shouldn't go telling people that 10w-30 is the new spec in light of such weak evidence. Jeepers come to JF for good information, just as I do. Other people's opinions can be a valuable source of that information. Mean Max may very well be right in that some AX-15's might shift better with 10w-30 (transmissions vary. I tried the lighter Redline MTL in mine and didn't like how it shifted), but until I see an official Jeep publication that says differently, 75w-90 is still the spec.
If it ain't broke... break it.