Comment Re:California Top-Two Primary (Score 1) 551
Oh, it's much messier than that, though that's usually how I vote. But consider an open-primary system where the Democrat incumbent is running for re-election and you have the option to choose which party's primary to vote in - you know the Democrat incumbent is going to win her party's primary (if there aren't any serious opponents), so the best strategy for the primary is to vote in the Republican primary instead, for the least electable candidate, whether that's a far-right Tea Party challenger or at least the second-tier candidate who doesn't have GOP machine money. That means that in the general election, your favorite candidate is running against a weaker opponent.
Gaming top-two is much trickier; there are more unstable ways to go wrong, but a lot of it has to do with the candidates' supporters spending money on various people from all parties in the primary.