What is the test for reducing damages under the lex fori?

The case of Wong v. Wei is somewhat distinguishable from the case at bar. We are not dealing with a case of international dimensions. All Parties are resident Canadians. Kirkpatrick J. applied the laws of the lex fori in an attempt to reduce the damages that would have otherwise been payable by the defendant. He did this in the context of a tort that had occurred on the other side of an international border, but held, nevertheless, that the quantification of damages was a procedural matter and, therefore, the laws of the Province of British Columbia applied.