Carlos, as a follow-up I just found this in an NPR story.
“In two cases, pilots flying in the U.S. late last year had their planes pitch down unexpectedly after departures. Both times, the crew disengaged the autopilot and were able to keep flying safely," NPR’s Russell Lewis reports. "In a third report, a pilot complained that the Boeing 737 MAX’s flight manual was inadequate and 'almost criminally insufficient.' "
So it seems that MCAS d disengages as a part of autopilot disengage. None of this detracts from your computer science perspective. Indeed Boeing seems to share your concerns about software and puts final trust in pilots. I would be very surprised that they ever put total trust in anything software driven pertaining to air worthiness on their commercial aircraft where it couldn’t be flown manually. I don’t speak or work for them, by the way.