I am shocked at how many boroughs are wasting taxpayers money on borough wide 20mph zones. One of the worst is Lewisham where in 2016 they spent £1.23m on one - results sent to their cabinet in September showed 'the average speed reduction was just 0.5mph'. In 2016-17 KSI data in Lewisham increased by 3%. Compare to say neighbouring Bexley or Bromley where they target these in very localised areas and there was a very sharp reduction in KSI figures. This is a terrible waste of money from a council. Drivers simply fatigue and lose interest, driving faster down high streets and outside schools and hospitals where they shouldn't really be doing more than 20 anyway. Campaigners regularly quote improved safety data where there are 20mph restrictions in place - but these are from localised and not blanket 20 zones. Poor results have also been seen in Brighton and Hove, Hampshire, Camden, Bath and North East Somerset and so on.
I am thus surprised that TFL is contemplating mass rollout of these on all its roads in Central London. I simply can't see a need for it or any sort of decent compliance on wide very open roads with central reservations such as the Old Kent Road or Euston Road. I would never dream of crossing these anyway without using the designated crossing. More waste from an organisation with a huge deficit.