The point about elections is that the 'winner' is based on who actually votes, not who could vote. If the 50% rule applied to local government elelctions then in the main no councils could be elected.

One problem with low turnouts is that anyone can say what a non-cast vote signifies without any fear of contradiction. We can just make it up. At the last General Election only 65.1% of the electorate voted. Obviously the rest were just too busy at work, but if they could have got to the polling station they would undoubtedly have voted for Gordon. You see, one can just make it up.

You have invented a 50% rule, but what actual difference would that make? In the last general elelction the Conservatives got 23% of the possible vote. Hardly a ringing endorsement, but they have still taken leadership of the government and have introduced some very unpopular measures. If I invent a 2/3 rule then the Conservative vote is "a joke".

Of course one can ask why people don't vote in elections, but generally this is not too clear, and currently there is no strategy to significantly increase turnout. We might observe the irony of Libya being bombed so that people there could not vote in elelctions.

Nevertheless, the struggle over pensions will run for quite a lot longer I think.