Cameron's reform the EU strategy.

 "Some expect my speech to pave the way for a fundamental reform of the European architecture which will satisfy all kinds of alleged or actual British wishes. I am afraid they are in for a disappointment. "Others are expecting the exact opposite and they are hoping that I will deliver the clear and simple message here in London that the rest of Europe is not prepared to pay almost any price to keep Britain in the European Union. I am afraid these hopes will be dashed."'

Angela Merkel

Angela sat on the fence in a very stateswoman like way. No offence given and no promises made to anyone. A little promise of some future bargain, of an unspecified nature on yet to be thought about terms.

Give it up Dave! Its not working. The idea of promising the electorate a future referendum but first demanding the EU change had some merit. We would all be better off if the EU worked better. Wasn't so protectionist. So bureaucratic. So regulating on unnecessary details and so lax on the important ones. If we could be part of a less idiotic union we would be much better off. 
The agriculture policies and free labour movement being just two examples of areas desperate for reforms.

But it isn't going to happen. 

As Mrs Merkel said the EU has bigger fish to fry. The EU crisis hasn't gone away and it can't be fixed until monetary union and a central control of Eurozone's treasuries and financial decision making is hammered out.  The EU is still not growing and unemployment won't come down. The European Union has a lot of work to do.

And the plan was flawed anyway Mr Cameron. 
The idea that if the UK just threatened to think about leaving the European Union it would be enough to scare Strasbourg into submission was never very credible. Its the same argument with Scotland. Threaten to leave if you like. But you won't get far.  And anyway, when the push comes, not enough people will vote to leave anyway.
So it wasn't much more than a way of trying to appease the UKIP drifters even when the think tank SPADs dreamed it up.

And now, of course, 3 years later, its just never going to work.

Because you have made a future promise. No referendum until 2017.
Quite a clever idea initially. Make the eurosceptics stay onside until after the next election. Give Europe time to recover economically. Force Labour to say something about their policy on Europe, when the Miliband policy is to say absolubtely nothing about Europe. Make UKIP look like spoiled children leading the UK to exile over issues that the grown ups could easily resolve.

But, with the Tory poll ratings well below necessary, the other EU leaders have nothing to fear.
The chances of a Conservative majority are are almost non existent.  Even a coalition is only a remote possibility. And a coalition of Liberals wouldn't allow a referendum. Neither would a Labour majority. So why would any EU leader want to open up a Pandora's box of demands and changes when there really is no need?

So it's a non strategy. Not really keeping UKIPers from desertion or driving EU change.
And worse, the public don't buy it either. because of that whole Cast Iron promise thing.

That was technically not a breach of promise. But then, neither, technically, was the Lisbon Treaty.
But since Iraq political 'benefit of the doubt' has been rather lacking.

So give up this strategy. Just promise the public a referendum within 3 months of the next election. Demand the other leaders make the same commitment, in writing, on air, in manifestos or openly challenge them to what they are afraid of?  Eventually, Labour will have to agree, probably going along with the Liberals on a stay-in platform. . And that then might just be enough to retain some of those defectors.

At the very least, even a lost referendum would finally get the EU issue out of the way and prevent the Tory split party happening for a decade or two.