The VTA is still defending its decision to build the phase-2 San Jose BART extension with a deep bore tunnel. They are being roasted on social media for the design of the stations, which would be as much as 90′ underground. VTA is pushing back, saying this is no big deal:
[VTA spokeswoman] Alaniz contends the deep stations won’t be a hindrance. Riders will have the option of taking escalators, multiple high-speed elevators or stairs at each stop. VTA estimates that even at the peak of rush hour it will take riders “less than a minute” to get from the platform to street level by taking the elevators, Alaniz said, while escalators will take between a minute and 90 seconds depending on whether the rider walks or stands. “A minute, to me, just seems extremely nominal when I think about a typical commute,” Alaniz said.
It is not clear where Alaniz obtained the 90 second figure, as it is significantly lower than what has been publicly discussed. A study of the downtown SJ station using simulation software showed it could take as long as 3.55 minutes to exit the platform, and 12 minutes to exit the station.
The simulation was done in the context of an evacuation. While one might argue routine rush-hour traffic is not quite the same as an evacuation, note that the simulation assumes the faregates and emergency exits are opened. In fact, Alaniz does not indicate whether the 90-second figure includes wait-time at the faregates.
The reason for the lengthy travel time is due not so much to the depth of the station, but the lack of exits. In a conventional downtown cut/cover station, there are exits heading off in multiple directions. These deep-bore stations funnel passengers through a single narrow chokepoint, which can easily back up.
Systemic Failure 
Q: How can you tell when somebody from VTA is lying?
A: Their lips are moving.