Take Another Look at ISA (Intelligent Speed Adaptation) – and Rule it Out
The economic crisis may temporarily have ruled out spending £30bn on a national GPS-based system to prevent drivers speeding but it would be better killed off before even more money is wasted.
Cost recovery projections – fatally flawed by fundamental errors:
(a) expectations of reducing casualties by a far greater proportion than are ever caused by speeding. (Derbyshire Police’s recent analysis, for example, shows speeding as the primary cause of only 2.6% of accidents.)
(b) claims that Stats19 understates the significance of speeding in causing accidents- in fact by including “possible” they overstate it.
(c) projections that without ISA, casualties would remain near current levels or rise – but since the report was published they have fallen substantially. Falls in casualty numbers due to any intervention of course relate directly to numbers before the intervention.)
(d) projections of further increases in traffic volume – but volume has been falling for several years and seems set to continue to do so.
Claims for effectiveness ignore:
(a) accidents caused directly by equipment malfunction and errors in GPS speed limit data, including recent or temporary changes.
(b) unexpected braking – a major cause of accidents - due to ISA cutting in when drivers, including other drivers, do not expect it – and a wide range of other problems when some vehicles are ISA equipped and others are not.
(c) many (entirely predictable) adverse effects reported by one volunteer driver – see below: