PMQs verdict: Miliband wipes the floor with Cameron

You can't tell how well Miliband is doing anymore, because the prime minister keeps on writing his script for him. The daily spasms of shambolic incompetence from No 10 mean Miliband could stand in the Commons and read out news articles if he wanted to. In fact, that's not far off his approach today, where he lazily and successfully attacked a visibly tired David Cameron. The fates point in his direction but, to his credit, there are flashes of the easy wit which suggests he's continuing to find his feet in opposition.

Miliband started with the energy policy Cameron's own ministers seemed confused and ashamed of. That prompted George Osborne to lean in and whisper something to the prime minister. "Oh look, the part-time chancellor is giving advice again," Miliband observed. "I'm actually coming onto one of his favourite subjects – the west coast rail line." The reference to Osborne's first class shenanigans, which were only just overshadowed by Andrew Mitchell's resignation last Friday, was well delivered. "It's not the ticket that needs upgrading, it’s the chancellor," he added.

PMQs jokes are always pre-scripted – our current generation of politicians are simply not witty enough to construct them on the hoof. But Miliband has mastered the art of making them sound impromptu. It’s a massive improvement from his robotic beginnings.

Labour MPs have taken to talking over Cameron's answers. Miliband was met in silence by the sullen and glum Tory benches. It's a telling difference. Cameron was worse than usual today. He lacked pace and his lists of government achievements were unconvincing. As the sessions wore on, he became irritated and his cheeks flushed red. "It's good to see the crimson tide back," Miliband observed cruelly.

Even where he was strong, Cameron seemed to slip up on his own banana peels. He finished one list of positive economic news with the assurance there was more to come. That's probably a reference to tomorrow's GDP figures, which he will have been given advanced sight of this morning. That hint will go down very badly with the Office of National Statistics (ONS). Mentioning it will also have boosted expectations, so they'd better be good. Even if they are, the media will (rightly) credit the Olympics and treat it as a blip.

He also won strong support from his own MPs for promising to stop prisoners getting the vote. He even mentioned another possible vote in parliament. It’s hard to see how that would help, but government spokespeople insist parliament is sovereign in this matter. If that's what they really believe, Cameron seems to be directly at odds with his attorney general, Dominic Grieve, who warns we could potentially be chucked out of the Council of Europe over the issue.

If you were charitable you would say Cameron shoots from the hip. If you weren't you'd say he screws up regularly. Charitable interpretations should be left to school plays and charity fundraisers. They have no place in Westminster.