Janet Street-Porter: No film will reveal the truth about Maddy

The idea that the McCanns are considering the possibility of making a film about the disappearance of their daughter bothers me for a number of reasons. The couple's spokesman has confirmed that talks were held with IMG, the company behind the highly successful dramatised documentary about two British climbers in the Andes, Touching the Void. Although Gerry McCann has tried to distance himself from the speculation on his blog, he did not deny that a meeting had taken place.

You can see why he might be circumspect – any suggestion that the Find Madeleine fund might profit from a piece of factual entertainment would result in an enormous backlash from members of the public, who broadly remain very sympathetic to the plight of the grieving parents. The McCanns will have spent more than half of the £1.2m raised by the appeal, with no real end in sight. In spite of £300,000 being spent on a team of detectives, and £80,000 on billboards and posters, no clue has emerged that brings finding their daughter a bit closer to reality.

But drama-docs, as they are known in the business, are a grey area when it comes to revealing the truth. There's a world of difference between a police-approved reconstruction on Crimewatch, and the dramatised chats between (for example) two mountaineers in dire trouble. Who knows what was really said when you only have one version of events upon which a reconstruction is based? Also, whether Gerry McCann wants to admit it or not, the whole point of drama-docs is that they are documentary-lite: emotive music, sophisticated editing techniques, and dramatic re-enactment can add to or detract from the pace of storytelling.

Drama-docs have the dramatic criteria of the single play, not the first-person diary told in real time. Their primary aim is to engage an audience who wouldn't sit through unadorned facts and a voiceover. You only have to take a look at Panorama to see how dramatic reconstruction is used to "sell" tough subjects. I get thoroughly irritated with fast cutting and the constant use of music behind footage on the series. How we enjoyed Stephen Frears's award-winning film about the Queen, with Helen Mirren mouthing bons mots in a head scarf and Barbour, whereas in the recent BBC documentary series HRH revealed little and refused to be part of some concept of "entertainment". Documentaries have to contend with unembellished facts, which is why Panorama's look at Madeleine's disappearance did not really work as a piece of investigative journalism. It was impossible to name a suspect without libelling someone, and the end result, while trying to be even-handed, didn't really tell the viewer anything substantial at all, apart from talking about the height of balconies and various sight lines. It could never say the unsayable – the possibility that the McCanns themselves might know something that they are not telling anyone.

Kate McCann has been vilified by some sections of the media, because she is attractive and strong of character. Somehow we want a babbling incoherent wreck, not a determined young woman who seeks solace in her faith. No matter how much she yearns for her daughter, though, to collaborate in making a drama-documentary about her will not bring her back. In fact, if Madeleine is still alive, it will make her captors even more determined not to give her up.

Diets that Hugh has inspired

I've been glued to my television this week by Hugh Fearnley-Whittingstall and his miserable broiler chickens. Last night he managed to get 60 per cent of the chickens sold in Axminster in one week free-range. It's easy to sneer at successful entrepreneurs like Hugh, who don't have to feed a family on a budget. But the truth is, we slather our faces in "age-defying" lotions, and yet we seem perfectly happy to give our children chicken that has stood in its own faeces and never seen daylight. You can eat well cheaply (if you learn how to cook) and as a nation we eat far too much meat anyway. If we made fresh vegetables, pulses and pasta everyday food and treated meat as something special, then everyone could afford free-range.

* If I had £35m, it wouldn't be used to purchase a lavish house in a cul-de-sac in Hampstead. An Israeli billionaire (well, you'd have to have that kind of money) has just paid that much for a detached villa, reputedly the most expensive new house in Britain. This palace will be occupied by one man, his wife, and their two children, but they will be able to enjoy a nightclub, a cinema, a hair salon, and a living room boasting a huge stone fireplace that is a copy of the one at Cliveden.

Inside, the décor is a rehash of classical architectural styles combined with elements culled from James Bond films, like gold mosaics in the pool, an armour-plated front door and digital security cameras everywhere. At 17,500 square foot you could probably fit 12 broiler chicken units or 20 council flats in the space it occupies, and you can be sure that all that air conditioning and electronically-operated doors and lighting won't exactly be running off environmentally-friendly technology like solar power.