Also, some questions about parliamentary governments (since I don't live under one and only have a fuzzy idea of how they work). Don't the many diverse parties usually end up grouping into two opposing coalitions? And don't you sometimes end up with situations where some small party ends up being disproportionally important because they are the "tiebreaker" that everyone is trying to woo? Or am I totally misunderstanding how things work?
Canada has only had two government coalitions in its past: the first was The Great Coalition which lasted from 1864 until 1867, before Canada was Canada. After Confederation this coalition ceased to exist.
Since Confederation there has only been one coalition government in Canada’s history: the Union Government of World War I (from 1917 to 1920). This was a coalition between the Conservative Party, led by Robert Borden, and Liberals and independents. The coalition was formed in order to broaden support for the Borden government and its controversial conscription policy.
On the whole the supposition that small parties are the "tiebreaker" is debatable because federal legislation votes in Canada fall under different categories: "free" votes and votes where Members of Parliament are expected to tow the party line. A free vote is a vote wherein the Speaker of the House declares that the vote in question is a matter of conscience, or else is too important for party ideologies to get in the way. Votes where MPs are expected to tow the party line are, of course, usually dictated by the party's ideology if not by the leader of that party. It is not uncommon to attempt soliciting votes from another party, but this tends to happen only when there is a bizarre imbalance between the seats held by the ruling party, the opposition party, and all other parties--i.e. the gap between seats held by the governing party and opposition parties is smaller than anticipated.
As of Canada's latest election, the Conservative Party was able to snag 143 of 308 seats in the House of Commons, therefore making it a "minority government": a government which has achieved a majority vote without having more than half the seats. However, it is rather
large minority, so we've not seen our government become truly impotent yet.
(Just rather dictatorial.)