One off dispensations from normal restrictions are NOT that extraordinary but a huge FAFF and not a run of the mill response to tech problems.
We have a Flight Crew Authorisation system which permits the captain to defer a specific list of defects if detected down-route at locations where engineering coverage is not available. Thus preventing AoG problems which would otherwise require an engineer's authorisation to resolve. They are all within the authorised deferral limits of the MEL. The benefit is that the captain has the authority to sign off on the ENGINEERING requirement of the MEL item as well as the OPERATIONAL requirement.
Don't know if this is what you were originally referring to but hope it is useful info.