I disagree. I think it's far better that referees in a league or county act consistently. Otherwise week 1's referee says in/outs and week 2's asks for offsides and he gets grief (or vice versa), then week 3's referee asks for in/outs and has to contend with over zealous CAR demanding he accept his offside signals.Ultimately it's down to the referee to delegate which of the duties stated in law 6 he delegates to his assistants, in theory The FA and CFAs should at most make suggestions.
As long as referees are consistent in their instructions to/expectations of CARs within each league it really isn't a problem.