Folks,
All this remind me of a long since retired BOAC/BA engineer, many years at Heathrow, always worked on contract customer's aircraft (was also a motorbike maniac, some of you may remember him) because he was so good at diplomatically handling "contract customer's crews".
He wasn't a bad AME, either.
Anyway, we arrived late one morning, having had a rudder defect in Bangkok, where BA's chaps swapped some boxes, and the defect "disappeared".
By Heathrow, now we had a another rudder defect.
On the ground, said chap, very patiently (as he always did) explained to the "engineeringly challenged Captain", ie; me, all about the defect, and what "they" had done wrong in Bangkok.
In the middle of the explanation, he realised that what he had said was a complete explanation of why what he had said could NOT be the "new" problem, and changed gears so smoothly in doing a 180, that even I was impressed. Not even a momentary pause in the flow of "explanation".
As a matter of interest, the real problem all along was not electrical/electronic/hydraulic, but a mechanical failure in a PCU, where they had never failed before, as I found out after a big delay 36 hours later.
Amazing what you find, when you get up and actually have a look. But it took an increasing less diplomatic Captain quite a while to convince "the chappies" that they were going to have to get the cherrypicker and have that look see.
Tootle pip!!