Valiant flight control feel system.
The Valiant had a rare feature providing the pilot with an ability to close down the flight control feel system which I recall was "Q feel". This indicated a lack of confidence by the designer in the long term viability of the system.
Were there any failures or bugs in service attributed to the feel systems? I think that I would rather have relied on Martin Baker to get me back down than my ability to land with an inoperative elvator feel system. Trying to land in manual was bad enough!!
I doubt whether squadron pilots would have been permitted to close down any of the three systems as without feel the forward weight of the yoke, if let go, would have been enough to pitch the aircraft over to a negative g value high enough to clap the wings together. This would spoil your day!.