Everyone knows that a shitload of new miles of road are about to be planted through California, particularly the headache areas of Los Angeles, San Diego, and the Bay Area. This is, clearly, a good idea intent on alleviate a lot of the fucked up traffic in these metro areas. Unfortunately, I'm thinking it's not going to make much of a difference.
Think about this... other than that really weird disappearance of freeway lanes between Orange County and Los Angeles County, the number of lanes on the 5, the 405, etc., doesn't really seem to be the problem. I'm actually of the opinion that there are plenty enough freeway lanes through Southern California. The bottlenecks (other than the one mentioned above) don't seem to be the interstates at all, it's the fucking exit ramps.
Seriously, how many times have you driven through SoCal and made decent time in the center or far left lanes. Yes, I understand you're still moving way under the speed limit, but take a look at the far right lanes... the ones that lead to off ramps taking you to Pico, Santa Monica, Olympic, whatever. THEY'RE ALL FUCKING BACKED UP.
And why? Well, shit, most of them only have one exit lane. If you're lucky, there might be two. What Los Angeles needs are off ramps that are two to three lanes wide. Yes, this isn't going to solve all the problems, as 3+ million people in one area is going to lead to bad traffic regardless, but damn... instead of worrying about those two or three spaghetti bowl interchanges, start worrying about those smaller bottlenecks called off-ramps. If people can get off the interstates quickly and efficiently, they won't be stuck on the interstate, backing it up, slowing down the other six lanes of traffic.
Of course, I don't really know much about urban or highway planning, but this sure as shit makes sense to me.