Monday, 24 November 2008

"What Boris has against London’s cyclists?"

A great piece of analysis from Boris Watch showing how the mayor seems determined to make London less safe for cycling...

He hasn’t answered the question. He’s dodged, ducked, dived, dipped and then dodged again, for good measure. He’s not offered up any plausible explanation for what was either a direct lie or the result of listening to and believing someone who was lying. I wonder why.

As for the facts put forward, there’s a glaring lacuna in there that renders this answer not only evasive but actually misleading. Basically, you can’t compare artic and non-artic buses by vehicle kilometre and use the results unaltered. It’s intellectually dishonest and here’s why:

We’ve seen from the London Travelwatch document that in order to maintain passenger capacity on debendification you need 40-50% more buses (in fact 75 bendies become 117 non-articulated buses on the first three routes, for a total increase of 56%, because the 507 and 521 are special cases). Presumably, if the bendy casualty rate is really only 32-36% more, then scrapping bendies and replacing them with 56% more non-bendy buses will *increase* the casualty rate and be less safe for cyclists. Let’s do the maths on a simple example:

Say intensive non-bendy route X has 10 collisions with cyclists per year and intensive bendy route Y, with the same number of vehicle km operated, and according to the Boris Ratio, 13 collisions per year. Total: 23 collisions.

Now, we debendify route Y, increasing vehicle kilometres by 50%, but reducing the casualty rate. We now have 13/1.3*1.5 = 15 collisions per year, for 25 collisions in total, so we’ve made the bus network about 8 or 9% less safe for cyclists.

It can be seen from this that no matter how the figures are dressed up and spun, the extra casualty rate on bendies has to be below the replacement bus rate, otherwise you end up injuring more cyclists.

I ask myself what Boris has against London’s cyclists? He seems to favour a lot of projects that actively harm them.


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