Well, there's a reason, it doesn't matter if it isn't good: other curious drivers. Here in Israel, traffic reporters on the radio routinely implore the listener

Well, there's a reason, it doesn't matter if it isn't good: other curious drivers. Here in Israel, traffic reporters on the radio routinely implore the listeners not to slow down and take a look, since it causes jams. My point is, whatever causes a segment of the road to only allow x cars/sec will cause a bottleneck if there are more than x cars/sec incoming flow, regardless of whether it is inherent or not.