SIR – No, Mr Thompson (Letters, March 31)! Think. The whole point of the research review with the Danish experiment was accidents reduced. People drove at safer speeds commensurate with conditions, not ‘faster’.

At no time did I or the research claim they drove faster but safer – a completely different perspective.

As to CO2 on the highway the combustion engine produces more emissions driven at inappropriate speeds. Unnecessarily slow driving prevents use of the higher gears or overdrive. Speed bumps necessitate changing down two or three gears and over revving the engine thus increasing pollution. Simple mechanics.

Godfrey Bloom, MEP for Yorkshire and North Lincolnshire, Main Street, Wressle, Selby