The analysis doesn't really hold true for Canada, and your facts are somewhat wrong. The smallest province had a 135k population by 2006 (last major redivision of the constituencies), 10 times bigger than your numbers (25-35k are more like the size of a small constituency in the smallest provinces). It is true that numbers favour the low population areas to an extent - constituencies in PEI have around 25K pop, while the rural provinces like Manitoba have around 80k and the denser provinces like Alberta, Québec, Ontario, BC have many urban constituencies in the 130-150k range (and most between the 80 to 100k range).

But the numbers don't quite paint the whole picture. E.g.: the Maritimes together have about a third of the number of constituencies of Quebec... and about a third of Quebec's population. Cities like Montreal, Toronto, Calgary, Vancouver have more MP each than the smaller provinces do.

We're a country of natural resources with a big and diversified territory. Some of the areas with low population aren't necessarily underdevelopped, and those MP representing 30k people can often represent more heterogenous interests than MP representing 100k people in far more homogenous city neighborhood often just a few sq. km in size.

It's true the system limits the number of viable parties and makes it nearly impossible for fringe parties to ever get seats despite sometime getting over 5% of the vote globally, but as for stability, or giving a lot of power to regions over the cities, it's not really true.

The low population/outer regions actually always complain that the power always resides with the areas of dense population and that their voices aren't heard, and the West always complained that the central areas held all the power (both are true, with nuances I'll spare you). Through most of the 20th century, power in Canada has largely resided with the central (and most urbanized, and richest) region (Ontario-Québec), with the rest struggling to get itself heard. Most prime ministers, and the majority of cabinet members, used to come from central Canada (often alternating between a PM from QC and one from ON). There was a time when the picture was indeed fairly stable, Ontario was largely liberal (with pockets of fiscal conservatives, and socialists), Québec alternated between being largely liberal and occasionally conservative and that pretty much determined the strength of the liberal governements.. or of a usually short-lived minority Conservative government. The strongest Conservative government we got, for 8 years (in the Reagan years) was Mulroney's, and it's the result of a wave sweeping Québec, the Maritimes and Alberta/the West and parts of Ontario, isolating Toronto... and the wave was the result of very different factors regionally. It's only with the debacle of the Conservatives in 1993 - a real tsunami - following the fiasco of the last constitutional round (and other regional issues) that's started to change, and radically so.

That would be a myth too as far as Canada is concerned. Stability was the result of the enduring strength of the center-left Liberal party far more than of the system. The voting picture can be utterly volatile since the 90s (far more so than, say, in the US).

There are very radical changes at some elections, even if the popular vote doesn't always change that much (regionally yes, globally not always that much).

Conservatives had 1 out 75 seats in Québec back in 1980, in 1984 they won 58/75... A landslide, after promising many things to Québec on the constitutional front. For his second term, Mulroney still held 169 of the 308 seats in Canada.

In the 1993 election, Mulroney retired in utter disgrace and the Conservatives went from that 169 seats to a whooping 2 seats, straight from one of the strongest governments of the century to being 10 seats short of even being recognized as a party by the Chamber... The oldest party in the country. It's exactly as if the Republican party virtually collapsed overnight in the US (and thought near impossible in Canada, much as that would be in the US) Regional parties emerged, the morally and fiscally ultra-conservative Reform in the West (the "old" Tories were wiped out from Alberta after over 50 years of holding the majority of seats there) and Bloc Québécois in QC. Overnight the picture totally changed, with 2 Conservatives, 177 Liberals, 54 Bloc Québécois (out of the 75 seats in Québec) 52 Reformists from the Prairies, mostly Alberta and 9 NDP (social-democrats, pretty far left for a Canadian party). A regional (and separatist) party was all of a sudden the Monarch's loyal opposition, as embarrassing as that was for them (the Queen might see worse soon). In 1997, the Reformists gained a few seats and the BQ lost about 10 then regained them later.

By 2001 and largely because they realized under the Reform platform and banner they had peaked and were stinking way too much of the US moral right for Canada, the party absorbed the remnants of the old Tories and took its name, and gradually pushed to the fringe its moral, evangelical or right-wing catholics. The unification of the economic right, coupled with the enduring strength of Bloc Québécois (and disgust with the liberals in Qc) from one election to the other resulted in a series of minority governements - both liberal and conservative, some lasting no more than a year, with the strength of the social-democrats varying greatly. In the meantime, Alberta got richer and more relevantly bigger, and thus got more seats (and now the power has shifted west... but total lack of support in Qc and Ontario prevented it for a while). We seemed destined to be stuck in that unstable situation forever (especially since the country was doing quite well nonetheless), and at the start of the last campaign it really look more of the same, but the picture changed completely in three wees. Bloc Québécois went from 49 seats to 4 when it was expected to retain most of them. The Conservatives who are the old Reform in disguise minus the most radical elements got close to "their" Mulroney years score with 166 seats. The Liberals who had 177 seats 15 years ago now have 34 and are in a serious crisis. The social-democrat NDP had 9 seats 15 years ago, and never had been able to find support in Qc until a recent by-election where it got its first, but overnight in 2011 it went from that single seat to 59 seats in Qc, and a total of 103 in the country, becoming the official opposition facing a majority conservative government. And it's not over... the NDP got elected largely because of the popularity of its leader in Quebec (people voted for the leader, often having no idea or interest who their MP was), only to see the guy die of cancer before the parlimentary session even began. Their leadership race is still ongoing with a solid candidate from Qc, but the party has its roots in BC and industrial Ontario and the chances of the guy are really up in the air...so go figure what will happen in 2015, especially if the NDP don't choose the guy from Qc.

The situation is hardly more stable on the provincial level, where we went from decades of having two dominant parties (one separatist and center-left, one federalist and liberal) to the rise of a fiscal right that very nearly went from having a handful of seats for many years to coming a few seats short of forming the government 2 elections ago (and relagating the separatists to third party for the first time since 1976) only to collapse in the following election and finally to disappear this year, where the separatist party (PQ) has gone through several leadership and orientation crisis in the last years - all this resulting in absurdly keeping in power the Liberals by default rather than choice, for the first time in a majority government after a few minority ones, despite them enjoying an historical and enduring low popularity... and now we have a fairly weak PQ just out of its biggest crisis yet, a second separatist party - this one socialist, massively impopular liberals, a new fiscal right/reformist party (CAQ( found by an ex-PQ minister and that is actually an alliance of federalist and separatist forces from the right that got spectacular poll results two months ago (to the point of being the "sure bet" next majority government of most commentators) to an equally spectacular (and very fast) decline in favour, and the separatist leader deemed finished by New Year's day - people were even foreseing the end of the party after this year's election... - but weeks later she's rebounded, to the point the polls have her and PQ win a short victory if the elections are next spring.