Pindi - the DP switch
was the cure, that plus revised actuator stops and improvements in wiring integrity. At the time, the RAF/MoD blamed EE for bad design of the tailplane trim system, even though the design had been, in Bee Beamont's words -
. . . investigated, approved and authorised by many tiers of officials. . . in the Ministry of Supply. The trouble was essentially mechanical in that the original SP trim switch could "stick on" causing the actuator to run to full travel even after the pilot had released the switch.
This is not to say that this "reason" was not given for future accidents but I seem to recall that the fixed, vertical tab on the back of the elevator could also give a similar effect if it had been bent or hand-filed to a wrong dimension. As this "job" was usually done after a 2nd line servicing I didn't have a lot of experience with it, maybe Luke or Love-Child can clarify.
Luke and SPHLC
Good tales blokes, as yet another Canberra rigger I can empathise with everything you say.
Luke
Glad you picked up on the Lady be Good thing. Here's a shot of that nav target from a 14 Sqn B(I)8.
Pic taken by Jim Sewell, 14 Sqn pilot.