Speed Limiting

I surely won't be the first person complaining(?) about speeding on the expressways. The most funny thing to notice is a group of cars in front of you slowing down suddenly because they see a cop car coming onto the express-way.
Sometimes you see that slowing group in your rear mirror.
But this slow-down is quite temporary. The cop-car whizzes past at about 10MPH above the speed limit imposed and as soon as it is out of sight, everyone is back to their speeding habits.
Ok..ok.. so you all know about it and I need not talk about it unless I have a solution. So I do :D
So instead of whizzing past, if the cop car actually got into the middle lane and drove at the imposed speed-limit, we have everyone in the middle lane stuck at that speed (cursing). The people in the third (and fast) lane would then as usual start moving fast past the middle lane people. But as they see the cop-car, their victorious smirk would be down to a understanding grin.
What say you?