It probably wasn't solely to annoy Polly that they held their poverty presser in Toynbee Hall but it must have been an incidental pleasure. Iain Duncan Smith and David Cameron announced the Tory welfare plan in that Edwardian palace of civic goodwill and self-improvement. I'm not sneering at either mind you, that's a trick you find on the professional left. But the venue was iconic, and part of the message-sending thing they enjoy doing – like Ed Balls eating the Kleinwort Benson canapes.

And it's always enjoyable watching IDS keeping a lid on it. A reporter asked whether it was wise for him to say on the radio that Brits were too lazy to work. Cameron made a joke about the Today programme and everyone laughed. But you could see a surge of the old warrior spirit in IDS. He does have a temper. That's quite attractive in a politician.

The PM was very much the Prime Minister giving the lead answer to all questions. That caused IDS to tighten the screws on his pressure lid occasionally. His policy has come through the fire, goodness knows how much table thumping, job threatening and knuckle whitening has gone into it. He has now expunged the shame of his career disaster – and in the same place that John Profumo expunged his. All credit to him, maybe his efforts really will prove to be the start of a cultural change in Whitehall's approach to the feckless incompetents who commission and deliver back-to-work schemes.

IDS has discerned a revolutionary truth: these contractors should not be paid unless they do what they're being paid for.

The PM gives his welfare message a good deal of wallop and it's clear to any fair-minded observer (I had to ask one) that he thoroughly means what he says.

He told us that he knew this country and refused to believe there were 5 million people not interested in working. "The system" must be providing the wrong incentives. If you were interested in twisting his meaning about – he was saying society did exist and that it was to blame.

The questioning wasn't what you'd call encouraging or even very supportive. And then there was chanting outside as of angry civilians who'd had their benefits tapered. The demonstrators turned out to be an Islamist goon squad chanting "David Cameron go to hell!" This sounded a little primitive, theologically speaking, to my untrained ear. The noisiest one declared, "No one has the right to make laws except Allah!" He didn't tell us what Allah's view was of the benefit taper rate on the Universal Credit. Some things are better left to Caesar, perhaps, or in this case Cameron.

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