Traffic isn't really an excuse. I've lived in the Bay Area for 13 years, and our traffic ranks in national rankings as some of the worst. With that said, during rush hour, from Downtown Oakland to Downtown Mountain View (880, Dumbarton Bridge, 101), the variance on my Commutes over three years was 52 minutes to at _most_ 1 Hour 15 minutes. 95% of the time it was under 1 Hour. The 1 Hour 15 minutes occured during a flash flood in which most major roads were having water issues. A few accidents pushed us to 1 hour 10 minutes.

Another way of saying this is if I planned to arrive 8 minutes early, I would have been on time 95% of the time for an appointment in Mountain View driving from Oakland.