The only reference to the "no upper arm support" matches I've ever seen are the ones Daryl has made mention of. I can see some "outlawing", or wanting to, the elbow on hip or elbow on ribs "full-tilt swiss position", as it is a rock solid position, but I am happy to allow it to those so constructed, even though the only way I could achieve either position would be under mechanical coercion, which would leave my body broken
! My point earlier was that even when I use a "normal" position even holding as far forward as the entry pipe, I still arguably have upper arm support on my chest (what used to be at least partly muscle), and to hold otherwise would require a comic book position with my arm almost straight out. Anyway, I agree, I would either comply with the rules or if that were not possible, I would skip the match, but I wonder if the rule isn't a little silly as it it much more ambiguous and open to interpretation than even a rule like "offhand elbow cannot touch body" or something of the sort.
I have heard people fuss about the swiss-style shooters many times, but often the people complaining are the ones that can't beat them
! To me, there is a big difference between mechanical and optical aids, both of which I consider cheating, and using one's physical makeup to its best advantage -- result of genetics and thoughtful training. Outlawing hold styles seems to me like requiring skinny people to puncture a lung or hamstring one leg before I will engage in a foot race with them.