The theory behind the rotating prongs and tube life is this: On a typical tube shooting slingshot like the S-9, for example, each time the tubes are released, they get bent or kinked at the prong as they pass through the fork, creating stress at that point that over time weakens the rubber. With the rotating prongs, as the tubes pass through the forks the prongs rotate around along with them, eliminating this phenomenon. I haven't done any formal testing of this theory, but I can tell you just from observation that the tubes on my S-9 and other fixed prong forks always eventually start getting small holes in the tubes right behind where they attach to the prongs (almost always on the left tube first for some reason), wheareas, the tubes on my FSX-FO do not. So the rotating prongs certainly appear
to be of some benefit. Great idea, though, to do some empirical testing of them. Who knows, you may find that the rotating prongs, while eliminating one kind of stress, actually exacerbate another (I haven't noticed this through casual observation, but you never know what more careful and controlled testing may reveal). Looking forward to the results.