Not only do I disagree over there being alliances over elections (because it denies people a free choice), but I object to the fact that the current system encourages them. If we had AV then Conservative voters could vote the way they want to (Conservative) and then vote Lib-Dem as a second choice _if that's what they want_. Similarly, Lib-Dem voters could vote Lib-Dem first, and then either Conservative or Labour depending on which they preferred as a second-choice, etc., etc.
That way the parties could concentrate on standing for themselves, and not what other parties are doing, and electoral bargaining could at least wait until _after_ the votes were in.
As it is, the election results won't actually tell us what the honest choices of the electorate are. People will be voting tactically, to keep out the people they oppose, based on guesswork over who has the most chance of winning. It's a horribly broken system.
(Not that I think that AV is the bees knees, but it's decidedly better than FPTP. I think my ideal system would probably be AV with an AMS top-up, but that's a completely different debate.)