It doesn't matter what the average is - the actual speed limit is between 40 and 55, depending on where you are. So if the speed limit is 40 and you are doing 70, that would be 30mph over.
Of course it does matter, because, as noted, it's the differential that causes issues. That why I mentioned the average. I never mentioned going 70 in a 40. But 15 over 55, if everyone is going 55, that unsafe. If everony is going 63 or so, then 70 isnt too big a difference. It's all about conditions. And that 45 person in a 55, they are a part of those conditions. Which everyone is responsible for being able to safely deal with.
And what he isn't mentioning is that the speed differential is inherently dangerous. If everyone is going 70 and paying attention it is usually safe. But if you have grandma in the left lane doing 45 because her turn is in 3 miles, then the speed difference creates potential for some serious crashes. Since grandma is complying with the law, that only leaves one person to focus enforcement measures on.
It's not the over by 5 mph'rs being pulled over and you know it. And you yourself mentioned that most of the accidents are happening during transitioning.... crossing over or pulling into traffic. Drivers exceeded the posted and expected speed limit make for situations where suddenly there is a car barreling on your that was not there the second before when you were looking left and right. I'll bet your bippy that that cop who was barreling down 4 at 80 mph and t-boned that teenager crossing over to enter her neighborhood was not in her vision in time for her to react and was certainly not in her vision when she looked, evaluated and committed to crossing. She died being burned alive because of a driver driving too fast on 4.
I even said it wasnt the 5 overs being pulled over. First thing I said, or the second. Pulling in front of someone doing 65 instead of 55, or even 70 instead of 55 is a minuscule difference. What was that officer doing? I think it was close to 100, or over 90. That's a huge difference over 55. She died because an officer of the law thought his lights and sirens gave him magical powers. Ah, found it, he was doing one hundred and 10 freaking miles an hour. In a 45. So, more than double the speed limit. Not really relevant to the discussion about folks doing 68-70 in a 55. Folks doing 120 in a 55, sure, throw'em in jail.
http://www.washingtonpost.com/wp-dyn/content/article/2009/09/12/AR2009091200063.html