Yes, Ken's done a great job - of spinning the facts

The train to London Bridge, which takes eight minutes off-peak, spent about 20 minutes inching forward, waiting in a long queue of its fellow trains for one of the station's magnificent three through-up platforms to become free. When I finally got there, there was a nasty argument with a penaltyfares Nazi before I was allowed past the barrier.

In the Underground, I joined a huge crowd kept penned in the ticket hall until enough space cleared on the platform. When I got down, there were seven minutes until the next train - at 8.30am. I had to let two go past, too full to cram into.

All the time, TfL loudspeakers hectored us with peremptory orders and bossy announcements, exactly the Orwellian soundtrack that Sixties science fiction films predicted would be in place by now.

At King's Cross, the new, improved interchange with Thameslink is actually about twice as far from the Underground platforms as the old one, a 15-minute walk with almost no signposting, two sets of ticket barriers, four escalators, and a flight of steps.

As the Mayoral election campaign really kicks off, and as I stood there in my crowd being harangued, Ken Livingstone's first words in last week's opening TV debate went through my mind.

"If you don't believe London's improved over the last eight years then you shouldn't vote for me," said Mr Livingstone. Well, Ken, coming back to the Tube after 18 months away, I was struck by how much more crowded it has become, and how little has been done to keep pace. I don't believe the Tube has improved, and I don't know anyone who does, apart perhaps from the manufacturers of shiny new wall tiles. Congestion hasn't improved. In central London, it did improve, after the arrival of the congestion charge, but now it is back to pre-charge levels. In the rest of London, it never stopped getting worse.

The housing crisis hasn't improved. The number of affordable homes in London is actually fewer now than it was when Mr Livingstone took office. We hear much of his famous target that 50 per cent of new developments should be affordable - almost never achieved, incidentally.

We hear rather less of something far more important, the actual number of affordable houses built. The fact is that every year of his term until last year, extraordinarily, Mr Livingstone achieved fewer affordable home completions in London than the Tories under John Major.

Labour's arrival in power was marked by the collapse of social house-building. Although the number of new affordable homes is now rising again, it is still nowhere near enough to make up for the loss of council properties under right-to-buy. In Mr Livingstone's time, the council house waiting list has roughly doubled.

The transport infrastruture hasn't improved. In their last 10 years, the horrible, evil Tories approved Thameslink, the Docklands Light Railway, the Jubilee line extension, the Heathrow Express, the DLR extensions to Bank, Beckton and Lewisham, the Croydon Tramlink and suburban electrifications to Hastings, Peterborough and King's Lynn.

In their first 10 years, Labour approved the City Airport branch of the DLR and an extension of the East London line. And Crossrail? After 18 false dawns, Londoners will believe that only when they see the first diggers cutting earth.

Fares haven't improved. According to the government publication Transport Statistics Great Britain, table 6.15, the average London bus fare has risen by around 50 per cent above inflation over the past eight years.

The environment hasn't improved. CO2 emissions in London continue to rise. Air particulate emissions, which kill thousands of Londoners a year, are at record highs in many places, and will rise further if the Mayor proceeds with his plan to exempt 80,000 low-CO2 cars from the congestion charge. (Most low-CO2 vehicles are diesels, which emit more particulates from their tailpipes.) Livingstone continues to approve brutal tower blocks, and is indifferent to the destruction of neighbourhood character.

Over the eight years as a whole, the buses have improved. Unfortunately, all the improvements - more buses, lower fares, higher frequency - took place in Mr Livingstone's first term (or, indeed, even before he ever arrived on the scene). The past four years have seen deterioration: the arrival of the bendy bus, the freeloading teenagers, the explosion in fare-dodging and a series of above-inflation fare increases.

Crime, too, may now be on the same trajectory. Again, there is no doubt that over Ken's term as a whole, the record has been good. There are fewer crimes (though police figures overstate the fall) and more officers, though they spend less time on the streets.

Now, however, the indicators are becoming more ambiguous. We may, just may, be at a turning point. For while police-recorded crime continues to fall, the other main measure, the British Crime Survey, shows an upward jump.

Mr Livingstone's real achievement, then, is not this fairly underwhelming record. It's his political brilliance in overcoming it. On affordable housing, for instance, he's somehow managed to focus the entire discussion so far around his attractive-sounding 50 per cent aspiration - not his less impressive actual results.

The very words of his opening statement in that TV debate - "if you don't believe London's improved, don't vote for me" - were a true mark of his genius. Of course London's improved - in the economy, the arts, the restaurants. But I don't see how Ken can possibly have played more than a minor part in any of that, unless we count Mayoral press releases as a new art form, or Lee Jasper's chums have opened a takeaway.

By claiming credit for the success of the entire city, Mr Livingstone is concealing his relative failure in those aspects of it for which he actually is responsible. And for all the electoral sound and fury of the past two weeks, if Boris Johnson and Brian Paddick continue to let the Mayor frame the debate like that, they will lose.