I have run my boat around the area. I was shooting photos and in order to hold position I popped the motor in reverse. The only way I would consider getting in the water would be if someone stayed on the boat. The current rips around that area. Many surfers have had to be rescued from Stinson Beach due to the currents and rip tides. That is also patrolled by the Landlord. My neighbor was bitten at Stinson Beach which is right around the corner. Not that I haven't surfed there and other local beaches myself. Vis is often not the best in area, but I have been able to see the bottom in Bonita Cove at around 15'...so not too bad. We hung out in Bonita Cove with a harbor seal and a couple of otters.
I have always thought it would be fun to drift into the SF bay on a very mild tide as close to high tide possible, along the Marin Headlands. Of course the reality is there is tons of fishing line, boat traffic, swirling currents and eddy's, along with other hazards I haven't even thought of, but the topography is probably awesome (Rock walls), and the area should be full of life.