I do know that drivelines twist. I am at least a little familiar with the failure rates of twisting driveline from repeted stress. I know of at least one Sikorsky helicopter (S 64) that measures power by driveline twist. But all in all very small amounts we are talking about here.
I thank you for not ragging on me and my intention is not to antagonize anyone here but what about the idea that the twist may absorb some of the shock and spread it out?