Personally, I see this attitude to be a serious threat to democracy. It suggests that certain ideas are not to be democratically debated. To suggest that the redrawing of Canada's borders is beyond the purview of the democratic process and may not be debated could lead to a slippery slope as such:
If we cannot reduce Canada's land mass, then some could conclude that any MP that beleives in any form of world federation should be banned from forming a government because he would intend to lighten Canada's borders with its neighbours.
From that we could then argue that any redefinition of provincial and territorial boundaries must be banned too (maybe we should even reverse our creation of Nunavut and give it back to the North West Territories).
Then from that we could ban any amalgamation or division of local governments.
In fact, why limit ourselves to changes in geographical boundaries. We could even argue that to believe in any change to the constitution is heresy, un-Canadian, unpatriotic, etc, and that any discussion of making any change to the constitution ought to be banned too.
From that, we could then argue that any party that wants to reduce military spending is un-Canadian, heretical, heterodox and unpatriotic, and so no MP holding such beliefs ought to be allowed to join in any co-alition either.
Then we could extend that to socialism. Socialism is anti-Canadian, heterodox, heathenous, treacherous, un-Canadian and unpatriotic, so any MP holding such views ought not to be allowed to form a coalition either.
Then we have environmentalists. If they introduce a carbon tax, it could hurt the oil industry, so again it's uncanadian, treasonous, heretical, heterodox, unpatriotic, treacherous, and showing a lack of love for Canada. Again, people holding such views ought not to be allowed to support a co-alition either.
Man, with that way of thinking, we'd have nothing left but one-party rule. But at least it would be the orthodox... oh, sorry, I meant Conservative Party.