I will also question why some people on this thread are obsessed with a stick shaker. This aircraft had a system that could have safely restored level flight had it been re-engaged. So, instead of putting a stick shaker in, why not allow the system to take control again if it is convinced that the aircraft is in danger of exiting the envelope?
There is a system, meat based, that at no additional charge and with no further engineering complexity, flies the plane. Going further into automation dependence seems poor path to follow.
Turning that into english, both the AP and FD are inhibited unless at least 2 IRU and 2 ADR are valid, amongst other things. If either pair
are invalid, engagement or reengagement of the AP would fail..
A/THR needs only the ADR condition valid of the above pair...
As I read your translation: so long as the IRUs are up and operating, and the ADRs return to "valid" once the icing in the pitot tubes clear and airspeed input becomes reliable again, the A/P can be reset.
Did I get that right?