I agree that you should use traffic calming and things like that.

But the method of increasing speed limits because everybody is breaking the current limit is clearly just bad engineering practice.

You start by over-designing and over-building the road, then you add spit limits to slow it down, and then you realize that everybody still speeds and you up the speed limit.

That just evidence of a broken culture around safety and road design. And people are paying for it with their lives.