Thom, I don't see how this helps, unless there's a flood. On an ebb, people will still want to hug the shore as they approach Red Rock - unless they're coming up from Raccoon and the ebb isn't too strong. Or am I missing something?
I think Dan's/Eric's idea of defining a "wall" like the Pinole Channel has potential. A line from G"3" near the long wharf to Castro Rock buoy (maybe with R"2" in between to bulge the line outward - also decreases the distance between buoys, making the line easier to judge) would have to be left to shoreward, no unwinding.
http://www.charts.noaa.gov/OnLineViewer/18653.shtml if you don't have a paper chart handy.
I had another wacky idea - not that I favor this, but just throwing it out there. Buy a couple of laser rangefinders. Get permission to station RC members on Long Wharf or the YB buoy station, and they can record distances and file protests.
Max