I finally discovered how to focus using those little squares in my viewfinder. I feel pretty lame that it took me this long - and even lamer that all my pictures up to now have been focusing on pretty much random things. No wonder I had such hits and misses. Of course, practicing focus points on a moving boat while taking pictures of other moving boats is perhaps not the easiest way, but it sure makes you fast. The Digital Photography School site had a very timely post about this yesterday and they use Canon for display purposes so I was able to follow along and set my camera up so that the AF button would track in AI Servo and I could just fire - the shutter is now a shutter and not a focus button. At least I think that's what I'm doing.
One of those close calls on the race course when a boat from another division crosses your nose. My focus is on the sail numbers.
Here we have put up the protest (red) flag, indicating another competitor has broken a rule. The focus is on the flag.
I saw a plane going overhead and quickly lined up this moving plane with my focus point, held and snapped.