Sketch: How did memory man do it without a loo break?

He said how his son had wanted 'dinosaurs' in his speech, without mentioning the unions

In the recesses of political party headquarters across the democratic world clever strategists are no doubt already frantically trying to come to terms with the true revolutionary meaning of Ed Miliband's speech yesterday: Is this the beginning of the end of the teleprompter?

Take one phrase. The content, to put it mildly, is hardly intellectually uplifting. But if you doubt Miliband's feat in making his note-free speech yesterday, try describing the Tories, as he did, as an: "incompetent hopeless out-of-touch U-turning pledge-breaking make-it-up-as-you -go-along back-of-the-envelope miserable shower", without glancing again at the words.

And this was only one line! In a 65-minute speech! Forget about "Professor Miliband" as one of his Harvard students describes him in the only-partly humanising broadcast Ed the Movie we were shown again in the build-up to his speech. This was on a different plane. You almost expected him to invite delegates to ask him when Florence Nightingale died or what the height of the Empire State Building is, like Mr Memory in the Hitchcock film of The 39 Steps.

Actually, his tour de force was more than that. It takes some chutzpah to come to Manchester, the bastion of 19th-century Liberalism and choose a speech by Benjamin Disraeli as your model. Especially when the now shamefully demolished Manchester Free Trade Hall where he made it – it's the Radisson Hotel these days, as Miliband reminded us – was on the site of the Peterloo massacre.

Nor is Disraeli's "one nation" idea exactly new to politicians in either of the two big parties. But if you're going to bury New Labour, and in a speech which mentioned neither Blair nor Brown, he was fairly unequivocal in saying that the last government had been "too timid" and "too silent" in the face of rich and powerful vested interests – then it probably make sense to use a great Tory Prime Minister as a human shield.

He did not as he claimed Disraeli did during that 1872 speech consume two bottles of brandy. Instead, freed from any notes, he stepped off to the side for a drink of water whenever the applause reached a crescendo.

In fact, he drank so much of it you wondered at the size of his bladder as well as his brain. But he described as eloquently as he has ever done his family roots as the son of Jewish refugees from the Nazis. He bravely revealed that he had been a Dallas fan—to the dismay of his father, the real Professor Miliband; and he described how his three-year-old son Daniel had wanted "dinosaurs" in his speech – without making any stale old references to Dennis Skinner or the unions.

In fact, there were some good jokes – including one about the gaffe-prone Mitt Romney's addressing him as "Mr Leader" – "sort of half way to North Korea" as Miliband put it. Largely the audience loved it. The polls show he has a long way to go with the country, but finally for the party, Mr Leader is beginning to rock.