John, “ Providing that the Captain understands and recognises the practical limits …”
Yes, recognition is a problem, part of communication.
Autos are ‘Dumb and Dutiful’, and unlike a human, generally they cannot tell you when there are struggling – they just quit at the limiting condition.
So the ability (of the crew), or inability (of the autos) to communicate are a potential problems.
Knowing when and what to ask the autos to do is an important part of being able to trust the system to perform as expected.
Thus, it may be that our expectation is a source of error. Do we expect autos to behave – think, react like a human because they appear capable of human like control and calculation (but without actually being able to think).
Not to reopen the AF accident here, but as an example, why should we be so concerned about a failure of the IAS displays and loss some flight envelope protections, whilst the aircraft remains flyable with a manual control system and attitude display?
Consider days of yore with piston power, crossing the Atlantic in icing conditions, no A/P, poor radar, systems freezing up (IAS failure), but the flights continued safety.
Why should we now focus on the failure of technology as a cause and seek to blame it as if ‘it’ was some third entity?
Why not re-examine the human, not for blame, but for change, things we no longer do, or can do. In these rare situations of technology failure, perhaps our expectation is that we should be able to do these things, but we can’t; does that mean we can’t trust ourselves?
That’s probable enough philosophical hot air to generate a Cb!