It was the Battle of the Boy Wonders in the Commons. In one corner we had Boy George Osborne, looking his usual 17¾ years old. In the other we had James Purnell, who looks about the same but is making an effort to age. His brown hair has taken on a greyish tinge (can you tint your hair grey?) and his chipmunk pouched cheeks are now flanked by sideburns. Yes, sideburns. That’s how desperate he is to be taken seriously. So it was Boy George v Boy James on the Budget. I think they are a bad influence on each other. They may be aged 36 and 38 respectively but the level of the debate often dropped to age 8 (no disrespect to eight-year-olds intended). Much of it was like a political version of King of the Mountain.

“Stand up and say how he would fund it!” shouted James at George, about the new winter fuel allowance, “Is he going to stand up and say how he would fund it! How would he fund it?”

He stared. George stared back. Maybe this was a stare-off. It was a nonsensical point, as the top-up allowance is a one-off and so won’t appear in future Budgets. But James didn’t care. This was politics. After a minute, he shouted: “He can’t!”

Yes, it was that grown up. But I got the feeling, watching them joust, that I was seeing the future. One day they will do this again, with heavier jowls and less hair. This mock battle, fought with plastic swords, was merely a portent.

Boy George wasn’t even supposed to be there, actually. I don’t think he could stand to stay silent any longer on the Budget. He had replaced the Shadow Welfare Secretary, the lugubrious Chris Grayling, who now sat on the bench next to him. Mr Grayling had good cause to be miffed: first Boy James stole his policy (on incapacity benefit) and then Boy George stole his slot. The Speaker, ever vigilant, missed the late change. He started the debate by calling: “Chris Grayling!”

George Osborne sat there, mouthing his name to the Speaker, like a goldfish with an identity crisis. The Speaker then shouted, as if at a rock concert: “Mr George Osborne!”

The Shadow Chancellor looked to be in the grip of Budget Fever, a virus in which the victim becomes obsessed with all things monetary and thinks it is completely normal to say things like: just look at page 72, paragraph 3, table 4, column 3!

He was despairing of the Budget, both the content and the strategy. He did not blame the Chancellor, who looked wan and exhausted yesterday, so much as the Prime Minister who had failed, to use the Tory phrase du jour, to fix the roof when the sun was shining. “It’s not the fault of some sub-prime estate agent in Mississippi that we enter a downturn borrowing £36 billion,” said George. “It’s the fault of the Prime Minister.”

It had been a deceptive budget. “Listening yesterday you would think that only the most polluting, the biggest 4x4s, are being hit. That’s not true. The Renault Espace, the Citroën Picasso and – would you believe it? – the Ford Mondeo!” New Labour used to try and woo Mondeo man, now they ended up taxing his car.

Now George was on to the welfare proposals and Boy James could not stand it any longer. “He says we are copying his proposals,” he sniped, sideburns glistening. “In fact it is the other way round!” Boy George insisted that wasn’t the case. They were, without doubt, having too much fun.

Times Recommends

• Lies and cover-up at MG Rover exposed by report
• High oil prices push manufacturing costs up
• Primark founder steps down as chief executive