Is a decision by an administrative adjudicator on a general question of law in the course of exercising its statutory mandate deference?

In Toronto v. C.U.P.E., (supra), LeBel J. said at paragraph 74: where an administrative adjudicator must decide a general question of law in the course of exercising its statutory mandate, that determination will typically be entitled to deference (particularly if the adjudicator's decisions are protected by a privative clause), inasmuch as the general question of law is closely connected to the adjudicator's core area of expertise.