I think Artificially LOW means a limit set below the 85th Percentile... Something like that.
There is some legitimacy to the notion, and it's an effective defense if you can prove the 85% of the traffic moves at a greater than posted speed on a regular basis.. I think.... It's all hearsay and such, I'm pretty sure I herd that this is how it works, and it is how speed zones get adjusted.
The notion that reduced speed limits save lives is a crock... Making a drivers license MUCH MUCH harder to obtain and require some REAL driver training... THIS would make the roads a safer place...
It's the same as all of your passing zones disappearing around the country... I see more and more NEW double yellows every time I am out in the country. It's gotten to the point where they aren't even to be taken seriously in some areas.