NewRedRider said:
It makes a lot more sense if you've ever lived in Atlanta. Their experiment does draw attention to the laws on the books. The ones that need to be added and more importantly, the ones that are never enforced. (i.e. Failure to yield to faster traffic) Germany has this one right. They give tickets to the guy/girl in the left hand lane. Not the speeder, unless it was a marked zone.
I've heard that they are very strict with reckless driving (including tailgating) as well. Reasonable speeding is not considered reckless driving.
check this out.... from
http://en.wikipedia.org/wiki/Speed_limit
85th percentile rule
Since the 1950s, traffic engineers have relied on the 85th percentile rule. The idea is that the speed limit should be set to the speed that separates the bottom 85% of vehicle speeds from the top 15%. The 85th percentile closely corresponds to one standard deviation above the mean of a normal distribution.
In practical terms, the 85th percentile speed is slightly higher than the flow of traffic. It has been observed that vehicles traveling over the 85th percentile speed (or faster than the flow of traffic) have a higher crash risk than vehicles traveling around or modestly below the 85th percentile speed.
In theory, the speed limit should be set below the 85th percentile speed only if crash records suggest an unusual hazard that cannot be mitigated by other measures such as restriping or engineering improvements.
However, in practice, speed limits in the United States are generally 5 to 20 MPH below the 85th percentile speed. This is partly due to political pressure, arbitrary laws or regulations[1], and the fact that many jurisdictions use the 85th percentile speed only as "guidance" or a "starting point."
One theory in support of 85th percentile speed limits, advanced by traffic engineers, is that drivers are, in whole, reasonable and prudent; drivers are able to discern road and traffic conditions, and thus able to select appropriate travel speeds in most cases. Therefore, even if the 85th percentile speed is above the posted limit, it can be prudent to increase the limit to the 85th percentile speed. (Note that traffic engineers do not argue that all drivers make perfect choices in all situations. Rather, they argue that the aggregate speed choices are usually reasonably safe.)