Well, the thing is, in order to make forward progress you have to get a solid foundation, and that includes dealing with lingering ghosts, legends (urban or otherwise), and a lot of stuff that can limit your search for those other avenues you mention. I've suggested another avenue of that kind—a connection between TKD on the one hand and certain Chinese arts, like Long Fist, which have similar spectacular, full extension acrobatic kicks. And we know that some at least of the early TKD Kwan founders did study Chinese systems, and it's the hard northern external systems, the ones like Long Fist, that are geographically relatively close to Korea and Manchuria, that have those kicks. I've said it before—I think that the Koreans happen to like kicking, period, and that's the reason they incorporate a variety of acrobatic kicks in their MAs—but it's at least possible that these neighboring CMAs, of the type I'm talking about, contributed something as well. It's something to investigate. Another possibility (which actually might be part of the first story) involves the role of Hapkido in the formation of TKD kicking. I don't know what the relationship between the two arts is, but at least one poster on MT has suggested that Hapkido kicking techniques were influential in the development of TKD's current kicking arsenal, and the relationship between the CMAs and Hapkido itself becomes part of the question. Finally, we know that tournament competition tends to promote spectacular kicks, when athletic difficulty is part of the point-scoring equation. It's not just TKD that shows this; it's happened in sport karate too and, interestingly enough, in Taekkyon, where the World Taekkyon Headquarters site specifically identifies many of the modern Taekkyon's high spinning kicks as the result of tournament competitive activities (remember that Taekkyon is now part of the official ROK sport council). So some (though probably not all) of the kicking components of TKD have arisen from the tournament career of TKD, maybe piggybacking on what I think is the long-time Korean interest in difficult leg techniques for their own sake.
All of these are possible directions for further exploration. But as long as people have this imprinted equation TKD kicking = Taekkyon influence in their minds, no matter how little good support there is for it, we won't be looking in those directions with much perseverence. So this kind of discussion is necessary, I think, just to clear the ground a bit.
