The Sketch: Cameron leaves himself susceptible to an 'urchin' who won't stay down

Over here we have the tall, well-dressed captain of the Upper Blues, popular with the grown-ups, easy way about him with the younger boys. And over there, that specimen is the head of the Lower Reds with the ears, teeth, and peculiar mouth. Not exactly swarthy, but not what you'd call properly English either. Something rum about him. Something clever. It's the clever ones you can't trust.

When you say to him in a pleasant sort of way, "Now look here, young urchin, you don't believe that, you're just saying it to be awkward." Then he'd reply, "No, I'm not. YOU'RE just saying THAT to be awkward."

And if you say, "Come on lad, you can't sit on the sidelines if you want to join the game. People will think you're an observer rather than a player." Then he says, "I know you are but what am I?"

And if you get annoyed and knock him over for some confounded piece of cheek, he jumps straight up again. Unforgivable! When you knock down younger boys they're supposed to rub their nose ruefully and apologise.

No, this one never stops his prattle, and it's enough to make a fellow testy because you have to knock him down again and to stop him bouncing up you have to put your foot on his neck and – damn, there are people watching. "Just a bit of rough and tumble, ha ha, yes, let me give you a hand, didn't hurt you there, did I?"

Right, that's enough of that. Cameron does have a problem with his opposite number. While much – if not everything – is on his side, he doesn't have a response to Miliband's "Go on, hit me again. Show everyone what a big strong man you are."

The temptation to oblige is understandable. But when angry taunting fails to complete the work, then a fellow needs something more cunning. The further danger is that any blow the weaker combatant manages to land echoes around the hall. One such happened yesterday. Cameron had chided Ed for his "pre-scripted questions" and then quoted from some friendly document.

In a wonderfully gentle voice, Ed suggested he not use "pre-scripted answers". It got a great cry of relief from Labour to see Goliath get one in the forehead.

There were exchanges on the NHS which neutral observers say were won by Labour. I thought he was winning until his line about whether the health reforms were covered by EU competition law. "He probably doesn't even KNOW whether it's covered by EU law," he crowed. "He just doesn't get it!"

Only too true. Neither did we, nor did his party.

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