Is it logical to have one speed limit for all vehicles?

[Silver Ghia]

I was just thinking about the logic of having one speed limit for all vehicles, on any one stretch of road.

You could be driving a brand new Merc with all the latest safety features, a Ferrari (or even a FPV) with huge stoppers, a 120Y, or huge B double truck. All vehicles are legally restricted to identical speed limits.

We have had rammed down our throats the fact that going only 5 kph faster than the speed limit severely increases the risk of accidents or injury etc. Authorities are using this as a reason for us not to speed. Obviously the ferrari and Merc in an emergency would be able to stop in a small fraction of the distance compared to the 120Y, and the B-double would probably just go straight through whatever they were stopping for.

A speed camera would penalise the Merc or Ferrari driver if they were going only 5-10 kph faster than the posted speed limit, but the 120Y or truck can legally travel at the speed limit.

What is the logic in the Ferrari and Merc being limited to the same speed as the truck and 120Y??

Perhaps the large trucks should be limited to only a certain percentage of any posted speed limit, to make speed limits more logical. I know there are a number of truckies on this site that would see RED at this suggestion, but why should they be able to go at the same speed as a high performance sedan when they can't brake, steer or handle nearly as well? Or alternatively, the higher performance cars should be legally able to go a certain percent faster, but I cant see that happening. Or maybe I've missed something.

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