@OK465
I think, if nothing else, the fact that until any two ADRs are back within 19 knots (< 20 knots) in a situation like this, the FDs are removed but remain physically selected and then can reappear, may just be one of a number of lessons learned concerning A330 systems functionality that may or may not be specifically relevant to the incident.
But that's not really the problem; it along with other matters this crew immersed themselves in was provided for in the FCOM and QRH procedures.
The failure of a crew to follow SOP's, to the extent that what happened here, was never envisaged by the designers, test pilots, or TRE's who helped to compile the appropriate documentation.
It really falls into the, "You can lead a horse to water, but ..." equation.