The Slipper Lake
To give you a general picture the wind was around 15 mph gusting up to 25mph in the direction of the green arrows. The control area is shown in yellow.
There was a significant chop which made tacking tricky and slow. The start line was heavily bias to port most of the time so being down the pin end was advantageous but not so if you got pinned out to the left hand side of the course. The course was a long beat to a mark into the sun which made judging port and starboard as well as mark rounding extremely difficult.
In the early races the ideal line is shown in blue. Start at the port end putting in an early tack and sail fast to a nice header off the headland by the google sign at the bottom of the picture. If you approached close to the mark on port tack you could just see the bow wake hit the mark and then you knew you could tack. Coming in on starboard was so difficult and the tendency was to overstand and lose time.
As the morning progressed the wind moved a touch anticlockwise and there were significant port tack lifts to be had by pursuing the left hand side of the course.
The run was tricky because at the gate where it says Emsworth Mill pond, the right hand mark was favoured but the wind could head and die as you rounded the mark. An early tack onto port at the gate was the ideal line but that put you directly into the line of starboard boats approaching the mark so you had to grin and bear the pain to clear the fleet. There was nothing to be gained by using the left hand mark.
The second beat was shorter but heavily bias to port so I have not shown it on the map, and then a final run into the gate and the tricky departure to the finish line which usually could be laid in one.