After a frustrating double flat on the Dars pop up ride ( not mine) I checked with my master mechanic colleagues concerning the design of the Zipp/SRAM hubs.  Yes, when you remove the rear wheel through axle to change a flat nothing keeps the components together !  Shocking but Zipp only cares about the aero properties of their rims, not the integrity of the cassette and hub pols which literally fell apart at the roadside.

Be careful with this high tech shit when roadside repairs are necessary.