What David Cameron and Kevin Pietersen have in common

Simples! Each occasionally produces a blinding performance and then promptly goes back to being absolutely rubbish for months on end, leaving their supporters scratching their heads in bewilderment as to why they lose their form so often and so disastrously.

Yesterday, Pietersen scored his second successive century in a One Day International against Pakistan, having been spectacularly useless against left-arm spin during the recent test series, playing against the same opposition. Yesterday’s innings of 130 was much better than the first – the big man’s display of controlled power was truly scintillating. But until last week, he hadn't scored an ODI century in three years, and God alone knows what sort of performance we’ll get from him next time round. The selectors have shown great faith and loyalty, probably on the basis that Pietersen, when enjoying one of his occasional bouts of good form, is a player who can turn matches by utterly dominating the opposition.

I don’t think anyone would claim that, even at his best, Cameron is in the same league. Decent performer, especially when up against exceedingly weak opposition (i.e. Ed Miliband). Now and then he produces a really good innings (the conference speech that won him the Tory leadership, his handling of the disastrous EU Greek bail-out shindig in December, and his “After all, it’s not like we’re brothers or anything” crack just before the Christmas recess).

But since then, it’s been like watching Pietersen batting against Ajmal. Even Nick Clegg is running rings round him. Nick Clegg!

Having fed right-wing conservatives (i.e. real, actual, proper conservatives who believe in stuff) a bit of red meat by refusing to sign up a series of daft and pointless EU financial rules, he has spent the last two months bending over his desk as soon as any Lib-Dem or EU leader hoves into view. What does he think he’s playing at by allowing that repellent jerk, Vince Cable, to hire a poisonously deranged leveller like “Professor” Les Ebdon (it’s the ever-so classless “Les” that truly grates) as the the Fair Access director for universities. Fair? FAIR??? Good God! – that’s like appointing Fred Goodwin as Head of the FSA.

Today, Cameron was busy telling the House of Commons that the partnership between England and Scotland had been “incredibly successful” and that he's keen not to encourage English “grievances”. Well, too late sunshine: the English have a list of justified grievances as long as your arm – after all, a Scottish prime minister and a Scottish bank chief between them managed to practically destroy this country’s economy. And I can assure Posh Boy that all of us south of the border have had absolutely bloody well more than enough of subsidising our neighbouring Socialist Republic. Grievances? A Scottish student can attend an English university and be paid for by my taxes, but if my son went to a Scottish university, I’d have to pay full whack – while, of course, also paying for the smug tartan twat sitting next to him.

You bet we’ve got bloody grievances, sonny!

Anyone who might have imagined that Cameron had grown a pair over the course of 2011 will have realised by now that he’s a flabby-faced coward without a conservative instinct in his entire body.

The main difference between Cameron and Pietersen is that the latter has actually won matches for England. Let no one forget that, during the last election, when faced with the political equivalent of a medium-paced short ball outside his off-stump, and needing a six to win, Cameron swung at it and missed it by at least a foot - and landed us with five years of what's essentially a Lib-Dem government.

I'd stick with Pietersen, despite everything, and drop Cameron, who really is proving to be an utter waste of space.