At a well known UK Charter airline I used to work for within the last two years; An engineer messed up the aircraft by incorrect choices and selections. During the subsequent MOR and QA investigations he is discovered to have made the mistake after some 18 hours of duty time.
In an effort to review the maintenance procedures and mitigate potential recurrences, the objective is so fudged by management, worried by the effects of a solid rule, that all engineers are now encouraged to work not more than 24 hours in any one day!
This was an actual 'procedure review' and the result was okay'ed by national airworthiness officials as they perceived something had been done.