I'm in the airline engineering business and we're mostly involved in fixing defects as they arise, or else sorting out the results of errors in design or construction. So, our approach is - if it was working yesterday and it isn't working today - what happened in the meantime?
Q1 What isn't it doing that it should?
Q2 What is it doing that it shouldn't?
The answers to these two questions provide the lead and from there on its detective work, mixed with a bit of inspiration. More like art than science? Sure; so I suppose we must be a previously unrecorded third type of specialist then...
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Through difficulties to the cinema