[speeder]

I think that several divergent but related factors come into play on that part of your drive:

1) Traffic just naturally gets more crowded, more cars/lanes/exits/etc., when you get near a big city.

2) Since there are a lot more vehicles and drivers, the chances of seeing some real jerkovs on the road increases diametrically.

3) The concentration of jerkovs/maniacs who just ran out of meth is greater in the outlying areas of a large city, (such as Santa Clarita, where you were), hence the lower quality of the driving gene pool. That's not to say that they do not exist in the middle of nowhere as well, just in lower concentrations.

That said, have you ever driven on Lake Shore Drive or whatever that "loop" highway is around Chicago? How about the Atlanta loop? Not defending CA. a-holes but it's a universal phenomena in my experience.