The c.g. was not further back than it normally used though, it would have been a normal aft c.g. for trim drag reduction, achieved using the tail trim tank
However that assumes parameters expected in a cruise regime.
If that normally stable attitude is upset for anyone of the various reasons already suggested, and we now have an a/c with a much higher angle of attack and a much lower airspeed than was ever reasonably envisaged in that trim configuration, then the influence of a rearward C of G may have a much greater effect on what the aircraft does and whether it is able to respond to corrective control inputs.
I'm out of my field here, but I do work with aircraft where C of G can be critical, especially in the aft region. That's all I wish to say other than to congratulate all contributors on the quality of depth of their discussions. I feel privileged to look on, and I apologize for my comments if they are inappropriate.
FOR