What is the Record for Judicial Review in Canada?

An American visitor to Montreal recently asked me "What is the 'record' for judicial review in Canada?" I chuckled, said "It depends" and directed her to paragraph 48 of Dunsmuir.

In Saskatchewan (Energy and Resources) v Areva Resources Canada Inc, 2013 SKCA 79 (which I have already blogged about here), the Ministry did not offer any interpretation of the provision at the time it made its decision. After a judicial review application had been commenced, the Ministry duly filed a supporting affidavit explaining its position.