All you need to know about our alternative government was contained in the Labour leader's off-the-cuff remarks before his recent speech at the London Stock Exchange. Introducing Ed Balls, the Shadow Chancellor, with whom he would be taking questions afterwards, Ed Miliband said: "You won't be hearing any reference in my speech to post-neoclassical endogenous growth theory."

He was talking about one of Balls's most mocked soundbites, possibly one of the most misunderstood political quotations of the New Labour years. It was a line in a speech written by Balls for Gordon Brown in 1994, in which Brown, the then shadow chancellor, said that "post-neoclassical endogenous growth theory is hardly the stuff of soundbites". The speech then went on to explain that this strand of macroeconomic thinking nevertheless supported New Labour's plans to use education to raise the quality of human capital and therefore the trend rate of growth.

Having poked fun at Balls, as a way of saying that he, at least, would not be spouting jargon, Miliband then launched into his closely argued thesis on the subject of "predistribution".

It is a paradox, is it not, that the candidate who won the Labour leadership with the support of young people holding placards saying "Ed Speaks Human" so rarely communicates in normal English? It is also peculiar that someone who dismissed suggestions of tension between him and Balls as "nonsense" should handle his Shadow Chancellor so maladroitly in public.

Miliband is addicted to an academic style of abstract thought that cannot easily be translated into everyday language, as the team working on his conference speech must know. Unfortunately, Labour's lead in the opinion polls provides little incentive for them to try. This time last year, Labour was three points ahead. Now Labour has been a solid 10 points ahead since the Budget in March, and Miliband feels that his dreadful conference speech last year Ω the one dividing companies into predators and producers Ω has been vindicated. "I was definitely right," he told Charles Moore, the former editor of The Daily Telegraph and an unlikely recent convert to the idea that capitalism is a terrible idea.

That interview did not start well, Moore reveals in the current Spectator. Nervous of technology, Moore tested his new voice recorder by interviewing his daughter before setting off for Primrose Hill to talk to the Leader of the Opposition. He then pressed "play" instead of "record" and heard himself say, "So, Ed, how come you're so much less glamorous than your brother?" And heard his daughter reply, "It's because I am made of Plasticine."

It did not end well, either. It finished with Miliband saying, "We  want a market economy, not a market society." Which is a slogan, not a policy, and only slightly easier to understand than "predistribution".

Despite all that, Labour is 10 points ahead. Partly, this might be because Ed Miliband, who used to step out of his London home to provide a clip for the television news on just about any story, disappeared over the summer and has rationed his appearances since. He has not tried to interrupt the Government as it provides endless headlines of splits and toffs, which are wearing away the already broken stone of the coalition.

There are many Labour supporters who refuse to believe the opinion polls. Maybe this is a reflex dating back to 1992, when the polls said Neil Kinnock was going to be prime minister, but people look for reasons not to believe the Labour lead. It is the mid-term blues, they say, an anti-government sentiment that does not reflect the actual choice in an election. Or they say you have to look at who voters prefer to manage the economy; or who they prefer as prime minister. Or they just say that Labour's lead is "soft".

Well, it may be. But there is nothing inevitable about governments recovering from mid-term slumps in popularity. And people may prefer the Tory team to Labour's on the economy, or say that Cameron has the qualities to be prime minister and that Miliband has not, but they take all that into account when deciding how to vote. The Labour brand is strong, even in tough economic times, because voters think that Labour would protect people's jobs.

It is true that if pollsters remind people of the names of the three party leaders before asking them how they would vote, the effect is a swing of about 1.5 percentage points from Labour to Tory, compared with the usual, unprompted, question. If that mimics the effect of an election campaign focused on the leaders, it may be that Labour's lead is really seven points rather than 10. But that would mean a Labour majority of 80.

So Ed Miliband may be irredeemably wonkish; he may say he looks like Wallace; but when people say that they intend to vote Labour, I am inclined to believe them. Miliband could well be prime minister in 2015. We should judge him this week in that light.

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