But the parallel actuators need to move the controls in order to get into an open-loop condition and extend the authority of the series actuators, this should be noticed by the pilot.
To create a demand that would cause the parallel actuators to move, an input from a sensor would be required or a demand from a pilot input (using the beeper trim for example).
Yes - one would hope that the pilot would notice that the contols were moving....but sadly that's not always the case.
Sometimes pilots don't physically monitor the controls, especially on the ground, and insidious movement, pehaps caused by a sticky trim switch or malfunctioning parallel actuator, might catch the unwary.
It's also worth saying that AFCS issues on the ground aren't confined to the AW101!