Macwood, not sure what you are referring to but one incident was as follows.
At Akrotiri, as nav rad, I usually did the seat and canopy pins so that I would be well practised in the event of a ditching. Now the canopy had a two pin system (for the uninitiated) and when safe there was a pin in the sear ejector ram. To arm the sear was removed and the other pin on the ring inserted so the a blade could press against it during the canopy jettison. I don't recall the technical details.
Any way on this sortie I had armed the canopy. Then, unnoticed the crew chief entered the cabin, opened the cover, removed on pin and inserted the other, in the process safing the jettison system.
If was one of those things done by touch as it was difficult to see.
The chief was certainly not disciplined and it was decided that nav roads should not do the pins.