It doesn't require the complex system to in fact break, or for you to forget your training, to introduce the possibility that a stressed human mind trying to start to appreciate an unanticipated possibility never achieves sufficient confident to diagnose and then act. The awareness of a complex intervening layer is in itself sufficient to frustrate intelligent problem solving, at least in a timely way.
Something to consider, for sure.. that intervening layer is always a 'head' problem
A 'big red button' which forced direct law, with direct law behaviour a set of memory items, would seem a reasonable last resort to offer a bemused crew.
Not forgetting appropriate display of unusual trim conditions and cancellation of any warning cancellations, naturally.
Radical, but reasonable