Here is PU's last message regarding the race. It explains why everybody started on port.
Quote
Well, thats over.

We did the Tornados first then the Stars.
Set the start line close to the breakwater so that if they started on starboard they could go about 4 tenths before they had to tack. That put them at the media tower at the east end of the breakwater.
The winds were around 15 knots so we set the weather mark at 125 degrees and 1.4 nautical miles. W2 (two laps) with a target time of 30 minutes.
All the tornados except Greece started on Port tack to go out for just one tack to the weather mark. Also there was more presure there. The Greek on Starboard went about 300 meters and ripped his mainsail so had to retire.
We misssed the target time by 20 seconds. (30 minutes and 20 seconds)
Spain won the gold.