I am from the alps, with my share of knowledge about frozen roads. I would add to that: "People drive more carefully on frozen roads, *if they are not used to frozen roads and/or know roads are frozen.*"
For point one: In Austria I have seen (local) cars drive 30 km/h over the speed limit on the Autobahn while it was snowing at sub zero, with exactly the same (too close) breaking distance to others. In my experience for many people used to snow/ice the speed limit is still the orientation for many during ice/snow. If anything I'd expect the increase in defensive driving to be offset by the increase in accidents due to bad view, longer breaking distances, etc.
As for the second point: In Austria the second it snows or rainfall happens at subzero amadas of snow/ice clearing vehicles hit the road, yet during my lifetime I experienced black ice multiple times. To those who don't know what this is, it is a invisible layer of extremely smooth ice coating the road, which can happen of air + road temperatures and rainfall just align in the worst way possible. The resulting road is so slippy as if god had toggled off the "simulate friction"-checkbox. I remember a time where no-one could leave my village because they couldn't get up that one hill on foot. I managed to get to school by stomping through half a meter of snow next to the road and slipped 10 times on the way to the school while wittnessing multiple (minor) car crashes. I have seen such conditions happen on the Autobahn as well and the results are not
pretty.
Zero traffic casualties in a cold climate therefore has to mean absolutely lightning fast road maintenance and/or stellar information on the current road conditions and is certainly an extremely impressive feat. I can't imagine this is possible without adaptive speed limits (and rhe infrastructure that is needed to pull that off). The Finns have reason to be proud (aside from them being really nice people in my personal experience).
I am familiar with black ice hving lived a large part of my life in Switzerland. Black ice usually involve having temperatures swinging around zero + rain. It doesn't happen if you are at -10°C.
Also. Finland has a long history of maintaining both dirt roads all year and ice roads in the winter on top of body of water so I guess drivers are much more used to them. It is also a relatively flat country.
I am from the alps, with my share of knowledge about frozen roads. I would add to that: "People drive more carefully on frozen roads, *if they are not used to frozen roads and/or know roads are frozen.*"
For point one: In Austria I have seen (local) cars drive 30 km/h over the speed limit on the Autobahn while it was snowing at sub zero, with exactly the same (too close) breaking distance to others. In my experience for many people used to snow/ice the speed limit is still the orientation for many during ice/snow. If anything I'd expect the increase in defensive driving to be offset by the increase in accidents due to bad view, longer breaking distances, etc.
As for the second point: In Austria the second it snows or rainfall happens at subzero amadas of snow/ice clearing vehicles hit the road, yet during my lifetime I experienced black ice multiple times. To those who don't know what this is, it is a invisible layer of extremely smooth ice coating the road, which can happen of air + road temperatures and rainfall just align in the worst way possible. The resulting road is so slippy as if god had toggled off the "simulate friction"-checkbox. I remember a time where no-one could leave my village because they couldn't get up that one hill on foot. I managed to get to school by stomping through half a meter of snow next to the road and slipped 10 times on the way to the school while wittnessing multiple (minor) car crashes. I have seen such conditions happen on the Autobahn as well and the results are not pretty.
Zero traffic casualties in a cold climate therefore has to mean absolutely lightning fast road maintenance and/or stellar information on the current road conditions and is certainly an extremely impressive feat. I can't imagine this is possible without adaptive speed limits (and rhe infrastructure that is needed to pull that off). The Finns have reason to be proud (aside from them being really nice people in my personal experience).