FPTP tends to hand a majority to the party that best appeals to the median voter. Usually there is a strong opposition as well. And then after 2 or 3 mandates, the governing party is normally cast from power. Those are all desirable characteristics of an electoral system, as I understand parliamentary gov't.
As for AB, I agree that it is a problem that parties there stay so long in power. But since that's not the case elsewhere in Canada, I don't think FPTP is the main cause.
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