The mechanism was a simple solenoid that restricted stick movement. I'd forgotten about the U/C interlock but there certainly was an IAS switch that I can remember making the stick chatter when flying around the changeover speed.
When Lee Jones led the RAF Aerobatic Team they were painted yellow and called the "Yellow Jacks". They scared the pants off me - particularly at the World Gliding Championships at South Cerney in 1964. They "wired the joint" at 4-6ft in criss-cross and at that height they couldn't have seen all other ac because the airfield has a distinct upside-down saucer shape