I think it's important to have a system that more accurately reflects the voting preferences of the electorate. Whether the result of any given election is one that I would like is up to the voters, and I wouldn't choose an electoral system on that basis.
However, to answer that point, and some of the concerns you've mentioned in other responses:
It's quite hard to say how previous elections would have gone under AV, as FPTP doesn't give sufficient data about voters' preferences. What we can say in general is that AV tends to reward parties/candidates that manage to broaden their support beyond their base and who avoid being widely disliked. So if AV had been used for recent general elections, it would have tended to benefit the Lib Dems (who would do well from transfers) while the Conservatives would do a bit less well as they tend not to get so many transfers. (This can be seen in the 2007 local election results in Scotland.) But of course, the ability of the parties to pick up preferences may well be different in 2015, particularly with the Lib Dems having lost a lot of their soft supporters. What is certain is that AV massively disadvantages the BNP, which is presumably why they're dead against it.
As far as "kicking the bums out" goes, I gather that AV tends to magnify the effects of landslides, so that (for example) Labour would probably have gained even more MPs in 1997.
AV does make safe seats less common. This is an important part of reducing the power of political parties (as they are less able to parachute favoured candidates into safe seats) and makes individual MPs more readily held to account. My experience of safe seats is mostly second-hand, as my party doesn't have any, but my experience of living in Labour-dominated central Scotland makes me think this is a definite advantage of AV.
As for No2AV's wittering about "behind-the-scenes deals", It's bollocks. AV is not a proportional system, and will not necessarily lead to more coalition governments than FPTP.
[Digression: In reality, most politics involves behind-the-scenes deals anyway. If a future election does result in another hung parliament, then all that means is the deals are much more open. Compare the Con-Lib coalition agreement to the Blair-Brown pact. The political model in which a governing party spends its parliamentary term implementing its manifesto points is woefully inadequate and naive. It's good that parties should develop detailed plans prior to the election (rather than waiting till afterwards), but what really matters is their main priorities. Whenever Clegg was asked about hung parliaments prior to the last election, he responded with his four main priorities, which have found their way into the coalition document and now into practice. It would be very useful for voters if all leaders were asked to be explicit about their priorities in this way during an election campaign, as this would provide a much better guide to their actions in office than a set of manifestos that no-one reads.
But as I say, that's a bit of a sidetrack. It would be more relevant if we were discussing STV or list PR, but AV is unlikely to lead to a future of endless coalitions. It's a bit of a red herring.]
Short version: whether you like or loathe hung parliaments, AV doesn't make them more likely. It does mean candidates have to work harder to appeal to a broader range of voters, and sitting MPs have to pay more attention to more of their constituents. Extremist parties do worse under AV, parties with broad appeal do better, and there are fewer safe seats.
no subject
However, to answer that point, and some of the concerns you've mentioned in other responses:
It's quite hard to say how previous elections would have gone under AV, as FPTP doesn't give sufficient data about voters' preferences. What we can say in general is that AV tends to reward parties/candidates that manage to broaden their support beyond their base and who avoid being widely disliked. So if AV had been used for recent general elections, it would have tended to benefit the Lib Dems (who would do well from transfers) while the Conservatives would do a bit less well as they tend not to get so many transfers. (This can be seen in the 2007 local election results in Scotland.) But of course, the ability of the parties to pick up preferences may well be different in 2015, particularly with the Lib Dems having lost a lot of their soft supporters. What is certain is that AV massively disadvantages the BNP, which is presumably why they're dead against it.
As far as "kicking the bums out" goes, I gather that AV tends to magnify the effects of landslides, so that (for example) Labour would probably have gained even more MPs in 1997.
AV does make safe seats less common. This is an important part of reducing the power of political parties (as they are less able to parachute favoured candidates into safe seats) and makes individual MPs more readily held to account. My experience of safe seats is mostly second-hand, as my party doesn't have any, but my experience of living in Labour-dominated central Scotland makes me think this is a definite advantage of AV.
As for No2AV's wittering about "behind-the-scenes deals", It's bollocks. AV is not a proportional system, and will not necessarily lead to more coalition governments than FPTP.
[Digression: In reality, most politics involves behind-the-scenes deals anyway. If a future election does result in another hung parliament, then all that means is the deals are much more open. Compare the Con-Lib coalition agreement to the Blair-Brown pact. The political model in which a governing party spends its parliamentary term implementing its manifesto points is woefully inadequate and naive. It's good that parties should develop detailed plans prior to the election (rather than waiting till afterwards), but what really matters is their main priorities. Whenever Clegg was asked about hung parliaments prior to the last election, he responded with his four main priorities, which have found their way into the coalition document and now into practice. It would be very useful for voters if all leaders were asked to be explicit about their priorities in this way during an election campaign, as this would provide a much better guide to their actions in office than a set of manifestos that no-one reads.
But as I say, that's a bit of a sidetrack. It would be more relevant if we were discussing STV or list PR, but AV is unlikely to lead to a future of endless coalitions. It's a bit of a red herring.]
Short version: whether you like or loathe hung parliaments, AV doesn't make them more likely. It does mean candidates have to work harder to appeal to a broader range of voters, and sitting MPs have to pay more attention to more of their constituents. Extremist parties do worse under AV, parties with broad appeal do better, and there are fewer safe seats.