Yeah, my wife and I live in the Los Angeles area, and if she's not on time for a job, she doesn't get hired back. So I'm not buying that. Sure, it might take four hours to go 10 miles, but if that's the way it is and you want to be there on time, budget five hours.
It's sort of like snow in Minneapolis. You have to plug it into every estimate you make about how long something is going to take. You'll notice that people in the twin cities never use snow as an excuse. Those in Los Angeles should take the same attitude toward traffic.
Having said that, I never drive into the city (from 35 miles east) if I can possibly help it, because even if you luck out and make decent time coming in, it's nearly impossible to get out. Going to a two-hour concert is easily a nine- or ten-hour time commitment. It's just not worth it. I can literally drive to Phoenix and back in as much time as a round trip to Santa Monica.