Most of the Bay Area HOV lanes are not limited access. They let you enter/exit wherever, creating congestion. They also slow down traffic at the points where

Most of the Bay Area HOV lanes are not limited access. They let you enter/exit wherever, creating congestion. They also slow down traffic at the points where people have to cross lots of lanes to enter/exit. When before/after studies have been done, the HOV lanes around here generally make everything worse.