Without investigating, I am prepared to accept that because of its design, the chances of an impact with passing rocks and sundry shrubbery are reduced. The range of stresses when such an impact does occur will stay the same however.
The physical stress that used to result in a ripped off or damaged mech, the stress required to bend the mech hanger, break the chain, or damage the spokes and so forth..... Where does it all go instead when there
is an impact?
It must be into the rear axle and/or the universal hanger.
Therefore, the rear bearings collectively will pick up the impact, maybe other parts of the bike.
SRAM tell us that the UH "will not bend" (exaggeration?), so that means any forces that are not taken up by the hub bearings
will go into the frame and/or frame bearings.
It could be that there are two benefits to be seen. One is the reduction in impacts. The second is the transfer to tough and hard-wearing hub bearings that may be more than capable of taking the load. In which case it really is, at the very least, a big evolutionary step forward. I don't believe that it's a re-invention of the drive train, but it is very clever.
I am also prepared to accept all of Srams's claims; they are after all legally bound to be honest in their claims. But they are not bound to reveal any downsides, that is for the customers to discover. Once upon a time, flexible stems had many positive claims. Darwin's Law applies to bike tech as well. So if we are all riding this Sram Transmission in five year's time, then the doubters will have been silenced and the early adopters will be justified in saying "I told you so!"
