Canada's Constitution enshrines proportional representation as a limit to the ability of Parliament to act alone in amending the Canadian Constitution in these areas.
The member is correct in saying that the jurisprudence of the Supreme Court has made clear that the court did not have a strictly mathematical or arithmetical approach for dealing with these issues and that it was not the only concern.
Issues related to electoral representation are sensitive. Canada has been able to avoid the American trap of transforming the debate about the electoral map into a debate about each party's partisan interests in setting boundaries in their own way. The Supreme Court has in fact created some flexibility, as long as we respect the spirit of the matter, if I may put it that way. In that context, it relies a lot on the concept of effective representation, as the member mentioned. For the Supreme Court, proportional representation is not an absolute. It is instead about the desire to effectively move toward that objective, but in a federation as complex as Canada, that desire must take into account other concerns as well.
That said, the flexibility for statistical or mathematical discrepancies between rural and urban ridings in the same province will always be greater than the flexibility that probably exists, in my opinion, for adjustments between territories and provinces overall. It's clear that a little flexibility can be leveraged. It already is and has been for other issues, so it could be as well for the issue of Quebec's political weight.