gums
All I know for sure is that we never had a problem with the Viper implementation since 1973.
If I have understood the system neither stick moved, so on the Viper also the PNF never knew what commands the PF was making, i.e. the Viper sticks are asynchronous in practice?
Concorde b.t.w. was electrically signalled but it was an analogue system with mechanical backup and conventional stick arrangements