Of course, this assumes that people know how to vote for the parties best for them. Which comes down to quality education and good news sources. You’d have to ban paid political ads, SuperPACs, lobbyists.
Then there’s the matter of voting fraud. Voting computers shouldn’t be used at all, all voting should be done on paper and the ballot design should be standardized. Voter registration should be done away with. On election day, all public transport should be free and workers should get at least one hour paid leave to go out and vote.
(None of these things are going to happen anytime soon, but I think they would help.)
Not for single-winner elections. STV (IRV) isn't so bad for multi-winner elections, but for single-winner elections it fails monotonicity. (It's difficult to design a multi-winner election system that's truly bad.) You think Florida in 2000 was bad? If there's a significant election skewed by IRV's problems, the population will want to burn the people who chose it at the stake.
IRV is a hack to incorporate run-off voting into the first-round voting system, and run-off voting is lacking.
In a political system as dysfunctional as the U.S., allowing voters to express true voting preferences is more important than having a voting system that will lead to only marginally better outcomes. Once true voting preferences are known, the political parties will have to adjust to accommodate that. As long as the voting system encourages some people to hide their true voting preferences, those preferences cannot push the two dominant political parties to change their platforms.
Of course, this assumes that people know how to vote for the parties best for them. Which comes down to quality education and good news sources. You’d have to ban paid political ads, SuperPACs, lobbyists.
Then there’s the matter of voting fraud. Voting computers shouldn’t be used at all, all voting should be done on paper and the ballot design should be standardized. Voter registration should be done away with. On election day, all public transport should be free and workers should get at least one hour paid leave to go out and vote.
(None of these things are going to happen anytime soon, but I think they would help.)
[1] http://en.wikipedia.org/wiki/Instant-runoff_voting