Matthew Norman: When celebrities swap jobs, career suicide ensues

If there are many difficult lessons to be learned from recent events here's one that even the most obtuse can quickly master: stick to what you know. Much attention has been focused on David Starkey's Newsnight self-immolation, and rightly so. If you go sampling the words of Enoch Powell, as The Beatles so nearly had it, you ain't gonna make it with anyone anyhow.

Given that his older brother Richard Starkey played drums on "Revolution", it's especially poignant that David didn't realise this. Yet it is our way to seek solace in dismal gloom, so both he and his sparring partner David Lammy will take comfort from this gorgeous symmetry. For even as the historian incinerated his TV career by blundering on to Mr Lammy's home turf, so the Tottenham MP ruined his political career by straying on to Dr Starkey's.

When Lammy dismisses Starkey as "a Tudor historian talking about contemporary urban unrest", he boldly reminds us of his legendary Celebrity Mastermind appearance. Among the then higher education minister's general knowledge questions that evening was this: "Who succeeded to the English throne aged nine on the death of his father Henry VIII in 1547?" The reply from David, who accuses David S of "breathtaking ignorance", was "Henry VII". In future, boys, listen to Uncle Matthew and stick to what you know. This episode of The Two Davids' Celebrity Job Swap is doing no one any favours.

* Still with that adorably scabrous old goat, another lesson beyond Dr Starkey's grasp is Denis Healey's tutorial on holes. "A large group of whites has started to behave like blacks," ran his post-Newsnight defence. "I think that is the most unracial remark anyone can make." Is it really, love? Is the inference that black people are inherently given to looting, and that in impersonating them white people are merely taking the spirit of Ali G to the logical next level, designed to make Martin Luther King sound like Eugene Terreblanche? Simply too close to call.

* One consolation about national shame is its penchant for teasing retired political titans out of the woodwork. Take Gordon Brown, who pitched up at Westminster on Thursday for the second time in a month. It was disappointing that Gordon had nothing to say about the riots, having controlled domestic policy for almost the entire lifespan of many of those involved. Still, his larynx won't have recovered from that impassioned speech in the phone-hacking debate. Besides, you have to prioritise. All it needs between now and Christmas is a nuclear reactor leak, a terrorist attack on the Royal family and a smallpox pandemic in Fife, and the annual cost of Gordon to the taxpayer will be down to £37,412 per special guest appearance.

* Also returning to public attention was Jonathan Aitken, who took space in The Times to laud the rehabilitative value of military jails. Fond as I am of the plucky born-again, in this context I'd rather read him on the importance of hands-on parenting. If the man who inveigled his teenage daughter into perjuring herself on his behalf can't speak with authority about the adolescent paramount need for strong paternal guidance, who in Jesus's name can?

* Fans of the Marxist definition of history, who may not include Dr Starkey, say a warm "Hi y'all" to the new favourite for the Republican nomination. If you're unfamiliar with Rick Perry, YouTube this drawling, smirkful Texas governor with a hotline to the Lord and a passion for executing prisoners, and see if he jogs the memory. Still the earliest of doors, of course, and this beauty is so sensationally right-wing (he can't be doing with welfare at all) that Dubya begins to resemble Hugo Chavez. But that distant rumbling from across the ocean sounds eerily like history lining up to repeat itself as tragi-farce all over again.

* Toppers aloft to the Alfred P Doolittle of gourmands. Michael Winner calls to discuss the imminent chiming of bells for his wedlock to the glorious Geraldine. Any plans, I ask, for children? "Yes, dear," says Michael. "We're planning to adopt loads of babies from Africa and Indo-China." Ladies 'n' gennlemen, I give you Britain's very own Brangelina.