My instincts and my reading tell me this is not the case, but I'm not well-versed enough in the issues to argue effectively. So I tapped someone who is; I invited Idealistic Pragmatist over to comment.
Since I don't have time to write anything original right now, I'll rerun their discussion here, and I'll invite MSS of Fruits and Votes to join us. MSS is a professor of political science who specializes in elections.
Here's the story so far.
...this is the reason I get cold feet every time someone waxes eloquent about proportional representation. Sure, sounds great when you imagine it's just Latin for "the NDP gets more seats"... till you realize it also means folks like this, who couldn't get elected God catcher under the present system, suddenly wind up guaranteed a handful of reps who will give cheer and encouragement to the like-minded as they wind up on the CBC every night, quoted ad nauseam in The National Post, and potentially hold the balance of power in a system that promises minority government after minority government.
They're out there.
Let's KEEP 'em out there.
Fortunately, this isn't actually true. Only two potential systems have floated for use in Canada, the one currently under consideration in Ontario (Mixed-Member Proportional) and the one currently under consideration in B.C. (Single Transferable Vote). BOTH of these systems have thresholds that would prevent small fringe parties from being elected unless they had significant support. Scroll down in my FAQ to the question about "small regional or ethnic parties" for the full explanation.
"BOTH of these systems have thresholds that would prevent small fringe parties from being elected unless they had significant support."
Yeah, and the GST was "revenue neutral". As you've pointed out, it's possible under the current system for these people to get elected, with "significant support". We've had upwards of, if I remember correctly, six parties in the Commons at any given time, and some of these parties have significant support out west. Anything that lowers the threshold of what constitutes "significant support" makes me nervous. It gives them a voice that would almost certainly bleed off right-wingers who figure at least their vote counts for something if they vote Tory/Reform/CCRAP, whatever. Empowering a move away from moderation towards fragmentation... cripes, isn't that trend bad enough in this country already? I certainly think so.
I suppose it's bound to come to this sometime. All I'm saying is when you're tiptoeing through the tulips of democracy, be prepared to step... or even slip... in the fertilizer.
My point is that proportional representation wouldn't lower the threshold for significant support--and in some ways, it would raise it. If anything, first past the post is far, far more dangerous in this respect than either of the two PR-based systems proposed for Canada, as the inflated seat count of the Bloc Quebecois indicates. We've been slipping in the fertilizer for years, and it's time to wake up and smell the democracy.
And your assumption about "more fragmentation" isn't particularly warranted if you look at what happens in other jurisdictions. It's not impossible that PR would create more parties, but I actually find that highly doubtful, given how many we have already (I suspect there would be a realignment of the current parties instead, with lots of politicians changing teams for a year or two). Regardless, though, there would still be less fragmentation under PR because it demands true intraparty cooperation within stable, majority coalition governments. If you're sick of the infighting and grandstanding, PR is actually the solution, not something that would create more of the same problems.
(See also six reasons to support proportional representation and myth #1: proportional representation leads to minority governments.)
You've done little to reassure me, I'm afraid. I understand how coalitions work — they're the issue for me. We effectively had one for most of Mulroney's tenure; he'd co-opted the sovereigntists and his constitutional and economic peddling to them and their eventual defection nearly brought an end to our country. Without their support, it's highly unlikely he would have won in 1984 and certain he wouldn't have in 1988. Thank God Harper has had the sense not to step into that mine field... but he does have to watch his step with them, all the same. I foresee even more dances with the Devil in a system that pretty much assures no single party in Canada will ever be able to plot a course without worrying about shoals around the fringe.
I look at Italy. The place has had nearly as many governments since WWII as it's had years. Israel is a country full of bright, progressive, educated people whose political process is perennially in thrall to a handful of people who really believe Samuel was right to denounce Saul for merely enslaving the Amalakites instead of killing them man, woman, and child as God commanded — a big part of the reason the place can never find peace with its neighbours or the rest of the people of the very same land.
Coalitions. And so a coalition between the minority Tories and, say, the Family Party? Would the recent vote on same-sex marriage been the non-issue it was under such circumstances? What would it mean for abortion rights? Immigration? The equality of faiths? The independence of the judiciary?
In the abstract, I love the idea of PR. It is more fair. It does give people more of what they want. But I'm not such a democrat and I'm not so generous that I don't look at what that means in practical terms in this country and look away in sang froid. When I think of what we have to lose, and I look at how close the example of that is even in a two-party system, I find myself retreating to the safer shores of known waters.
Feel free to jump in. Fact, opinion, gut reaction - all are welcome.