[superuser2]

Thirty minutes of time on a BART car, sure.

Suppose you live in the premium housing really close to the BART, so your walk is only five minutes to the station. Then another five getting through the fare gate and waiting for your train. Then your destination is an easy ten-minute walk from the BART. Great, but that's not a 30-minute trip, it's a 50-minute trip.

[sjdchid]

Granted, this is true for the more distant cities. But if I'm going to San Francisco or Berkeley (let's be honest, where the hell else would I want to go), the train ride itself is less than 15 minutes.