HN39,
You said C * :
This means that the feedback of the control law changes at a speed close to 200 KT (not mentioned by AIRBUS in our reports, to my knowledge).
To lower speeds the
pitch rate is used in the feedback; at high speeds feedback is using
G.
When the speed is correct, with 3 correct ADR, the smoothing of the two feedback goes well.
But in the AF447, speed selected for that smoothing is either false, or switching from one value to the average of two dissimilar, then the feedback leaps and bounds in the loop! 
Therefore we must expect APC / PIO (aircraft pilot coupling / pilot induced oscillation) !
1. The initial PIO pointed to by Machinbird may be born of such a discontinuity.
2. Other APC have been born then at the option of pitot failures (curve of the three speeds is very discontinuous) creating "non-surmountable" (CVR) instabilities in pitch and loss of control.
3. The very rapid oscillations of the parameters from 02:11:40 may perhaps be explained as well. We never got to overcome the possible output of the stall and we never discussed these oscillations that trouble me since I've seen these oscillations.
