Experts behind the £2.5 million plan to ensure motorists' speeds are constantly monitored along the A9 main route to and from the Highlands claim the scheme will reduce the number of crashes by 19% in its first 12 months.
Details of the plan were unveiled yesterday by the A9 Safety Group, a think-tank set up by Transport Scotland to devise methods of reducing casualty numbers on the notorious road, which claimed 58 lives between 2008 and 2012.
Banks of cameras are likely to be installed roughly every three miles on the 136-mile stretch from Dunblane to Inverness, making it the second longest system of average speed cameras in the world after Australia.
Motorists caught exceeding 60mph or truckers going over 40mph will face a minimum three points on their licence and a £100 fine.
The initiative follows the success of Scotland's only other average speed camera system, on the M77 in Ayrshire, between Bogend Toll and Ardwell Bay, which has reduced fatal crashes by 46% and serious accidents by 35% since it was set up in 2005.
While the A9 Safety Group's research indicates a more modest impact on the A9, with only a 19% cut in all crashes, from fatal to minor accidents, this is being described as a "conservative estimate" for the first year.
Nonetheless, dozens of accidents and the deaths of around two road users could be prevented in the first year if existing trends continue.
Latest figures show there were 689 crashes on the A9 between 2008 and 2012 - the equivalent of 138 crashes a year - with 0.084 fatalities per crash. A 19% cut should mean around two lives saved.
Experts argue that the cost of the scheme would be only £600,000 more than the £1.9m cost of each fatal accident to the public purse.
The Safety Group, which includes representatives from the police, councils, and transport bodies, stress that the scheme would "more than pay for itself" within the first year. The cameras are being rolled out in conjunction with the wider safety improvements to the A9, most significantly the £3 billion upgrade which will transform 80 miles of single carriageway into dual carriageway - though this won't be completed until 2025.
Other initiatives, such as increasing the speed limit for lorries from 40mph to 50mph to reduce crashes caused by frustrated motorists making dangerous overtakes, have been shelved but not ruled out.
Speaking as the plans were outlined in Dunkeld yesterday, Stewart Leggart, the group's chair, said: "We recognise there have been some issues raised, especially around the decision to keep the current HGV [heavy goods vehicles] speed limit of 40mph when the cameras are introduced. "We have not ruled out the introduction of 50mph speed limits for HGVs if evidence supports this. However, for the time being, the best available evidence suggests that cameras with a 40mph HGV limit will bring the greatest safety benefits."
The decision to stall on changes to the speed limit had frustrated hauliers as well as motoring organisations, while Highlands MP Danny Alexander dubbed the Scottish Government's announcement last month that it would introduce average speed cameras as a "knee-jerk" reaction and questioned the likely benefit.
A safety campaign about the dangers of overtaking on single carriageways, which accounts for 77% of all fatal and serious injury crashes on the A9, is also planned.