Great video. The u-joint is one of those things that works in practice but it is really pretty crude once you start analyzing it. Even way back in days of the MB and GPW they had the sense to use CV joints! IIRC, the Bendix joint was kind of weak but the Rzepa had good stength. How did the 4x4 industry manage to go backwards in joint technology? Probably all cost driven, same thing that made me give up on getting RCV shafts.