Jonathan,
One thing Shen's memory didn't bring up, and you would need to check
Coast Pilot 7 to confirm this, is that the USCG has designated those TSS
areas in SF Bay, as narrow channels.
In essence, this restricts the ships to staying within the TSS, as well
as telling the small boater, the ship cannot maneuver outside of the TSS
and I don't doubt you can see how this can alter a vessel's actions
versus an at sea TSS.

otn