Sorry to bring these comments up again
So in theory it's not that difficult to devise a software that automatically
As someone who has a Software Eng Degree, several years commercial experience with industrial strength, fault tolerant, 'mission-critical' applications (I hate that phrase too) and an ATPL I feel that it would be almost impossible to create such an application.
For a start that the aircraft would need to be fitted with so many sensors that its drag curve would be a vertical line. A database of global obstacles would be so onerous to create that it would be Terabytes of data and commercially un-maintainable.
In short we forget how wonderful the MkI eyeball attached to the Mk10 human brain actually is to sense inputs (topography, wind, aeroplane charactersitics) and meld these with prior experience to produce a safe and effective plan.
I do agree that the best the aeroplane's onboard computer can do is target Vref (or stick shaker = Vref + a bit for the technically minded) for the instantaneous inputs it is receiving.
Hope this helps. Oh and another well done to the BA 777 boys and girls! Those MkI eyeballs and Mk10 brains sure do work well under pressure!