Aero, Your comments stir some thoughts: initially, yes the FD should be the same as the autopilot.
However, reconsidering, certainly for the 146, the FD does not use the same control law nor the same mechanism of control, - autopilot servomotor vs muscle; thus there could be a difference - static / dynamic.
The FD is optimised for the manual task, whereas the autopilot has to consider the control system lags without all of the feedback cues available to the pilot - visual, seat of the pants.
Sidestick, the hazards of guessing #2, i.e. you don’t know, is that misleading speculation and personal technique can lead others astray. Always reference personal techniques to the manufacturers advice or the design principles - if in doubt ask them. The choice of FD reference may make a significant difference to either to the accuracy or ease of flying the system - reduces the tendency to hunt around a datum.
Also, unless you have an approved system for takeoff, or a very sophisticated computation for ‘head down’ landing, tail strike should not be a consideration. Tail clearance during takeoff is a true geometric attitude, opposed to a computed - desired value from an approved FD.