I took a short movie from atop the Arc de Triomphe. We had noticed that many of the largest streets and interchanges in Paris had no lanes. As I say in the little video, they would just be a distraction.
On the other hand, we also didn't see any accidents. So the chaos system is not actually chaos. But neither is it government-controlled, in any important sense. (I suppose the gendarmes would come if there was a fight, and a tow truck would come if there were casualties, but that's it).
If you just leave people alone, they can figure stuff out.
Anarchy is not chaos!