deSitter,
My piloting background is limited to Piper and Cessna, but I have 40+ years in all levels of computer software, hardware, testing, etc. on systems of various sizes. I agree with your take on giving the human the option to shut the computer out of the loop. Our ability to implement complex computer systems surpasses our ability to sufficiently test them or to fully comprehend subtle changes made to software. It is not that people are incompetent, or that excellent tools are not available; it is that we are not perfect, and neither is the software we develop. Minor miscommunications and software glitches brought down an Ariane V, destroyed a Mars lander, forced F-122 fighters to return to base, caused an Airbus to make an unexpected descent, and updated our smart phone clocks incorrectly. I, for one, think there should be a big red "Give Me The Helm" button because there will be more incidents - we just don't know what they will be. I agree, too, with your description of people frozen by unexpected or irrational results - the "deer in the headlights" - especially in times of high stress.
Thanks to you all for the exceptional information on this site from obviously very capable professionals. It is a tremendously enlightening and rewarding read for this VFR pilot.