Originally Posted By: ekpolk
Steady everyone...
Sunday night, I got a vivid reminder that it's not "speed" that kills, but rather, "relative speed". As described in my "venting about being vandalized" thread, I had to drive home from New Orleans (~200 miles to Pensacola), at 50-55 mph because that's as fast as I could go without having the wind blast suck my impromptu patch out of my shattered passenger window.
This drive is 97.5% I-10 east, through LA, MS, AL, and then home to FL. I felt like a super-vulnerable target the whole way, with cars blasting past me often doing more than 30 mph faster than I was. On several occasions, I prepared to swerve for the breakdown lane, wondering the fool barreling down on me would figure out that I was traveling slowly. I don't like the driving with flashers thing, but I put them on several times to get attention when needed.
High speeds (within some semblance of reason) are perfectly safe, especially if everyone is at about the same speed. Low speeds can be drastically dangerous if the low speed car is an unexpected obstruction to the rest of traffic flow.
ekpolk, you say that high speeds are safe, but you do not mention the context, which makes all other variables free. As a consequence, to show your statement to be false, I can alter all other variables to create a context that is false, assuming that one exists.
Theoretically speaking, it is possible to be in bumper to bumper traffic while traveling at 100 mph. Practically speaking, that does not typically happen. We all know that if everyone had their bumpers, for example, a foot apart from one another while driving at 100 mph, there would be collisions galore.
Speed has little to do with safety when it is within the design limitations of a given road. What has to do with safety is the vehicle density and whether or not the speeds are within the design limitations of a given road.
We do not have roads designed for speeds in excess of 85 mph in my state (and to make a strong statement, states in the union generally do not have roads designed for speeds in excess of 85 mph), which is partially why we do not have vehicles traveling bumper to bumper at 100 mph on our roads. The other part is that collisions only occur when two objects make contact, and as the density of vehicles increases, so does the probability that they will make contact.
Admittedly, it would be very difficult for a high traffic density to occur on a road that has a 100 mph speed limit, but my point is that high speeds are not necessarily safe and that their only correlation to increased safety comes when they make it possible for cars to maintain greater distances between one another, as to be quite honest, if you are driving a car and your car is the only car on the road, what can you hit? That is not a realistic scenario (and that is a rhetorical and perhaps philosophical question), but it makes it clear that your car's proximity to other cars is what enables your car to collide with other cars and the more isolated a car is from other cars, the less likely it is that there will be a collision. Raising the speed limits of major highways to their design limitations (preferably only on days when it is not raining) accomplishes that as a consequence of the equation I posted earlier.