Sure enough, counsel for the losing party in Pastore v. Aviva Canada Inc., 2012 ONCA 887 made an application for the Ontario Court of Appeal to re-open the case, on the basis that account had not been taken of the concurrent jurisdiction innovation (which appeared after the close of argument in Pastore and before the release of the ONCA's reasons).
Counsel for Aviva argued that the standard of review should have been correctness, based on the concurrent jurisdiction created by the Insurance Act (Ontario) between arbitrators and courts.
The ONCA did not address the merits of the argument. Only in a limited set of circumstances, not present here, would a previous decision be re-opened:
 Without commenting on the merits of these submissions or others that might be made, it is clear that the parties do not agree that an error has been made on the issue of standard of review that the court is required to correct, as occurred in Gore Mutual Insurance Co. v. 1443249 Ontario Ltd. (2004), 10 M.V.R. (5th) 67 (Ont. S.C.), the authority for reopening cited by Aviva. In that case, a critical subsection of the section of the Insurance Act under consideration had not been cited to the court, causing its decision interpreting the statute to be wrong.
So it begins... Although this court is not functus officio because the order of the court has not yet been taken out by the parties, this is not the type of rare circumstance where it is in the interests of justice to withdraw the reasons of the court and rehear the case on the merits.