She finished seven points clear of rising star Marit Bouwmeester from the Netherlands. The pair have been regular training partners and credit each other partially for their successes here, and will work again in the build up to next month's Skandia Sail for Gold Regatta at Weymouth and Portland.
Both have been on carefully structured and executed programmes, even if there are contrasts between their approaches which mostly reflect their different ages and experience.
Multala, 33, has done just the two ISAF Sailing World Cup regattas Miami and Hyeres this season, both light wind events, and came to Largs charged up to retain her title again. Bouwmeester, 22, has been racking up the miles and learning venues, strategies and scenarios for the future with coach Mark Littlejohn.
A fitting finale would have been most welcome, but the racers stayed on hold since Monday . Yesterday there was next-to-no wind and today there was too much. The Clyde was a mess of marching, charging white horses and flecks of spume whipped up by the muscular easterly of more than 30 knots with many angry gusts of 42-44 knots making racing impossible.
Finishing in third place was the USA's 2005 World Champion Paige Railey tallied on the same points aggregate as France's Sarah Steyaert, the 2008 champion.
Men's Laser Radial World Title Stays in Poland
Poland's Marcin Rudawski was surprised to win the Men's title last year in Japan, but was doubly pleased to repeat his success here in Largs. His upwind speed and fitness, a by product of two Olympic campaigns in the full rig Laser Standard was key to his consistency, winning four races from six starts. Disc injuries to his back has seen him twice come close to quitting sailing, but the lure of competition has always drawn Rudawski back, and he pledged to be back in La Rochelle, France next year to bid for his hat trick.
Sari Multala (FIN): "I am pretty happy really. It was a pretty nervous day for me. Except for the one race for me the best thing has been able to sail consistently and that means being able to come back when I have maybe been not right in the top group at the beginning of races and in all kind of conditions. It's been about both speed and tactics, but perhaps mostly about tactics. A little bit of boatspeed at times."
Marit Bouwmeester (NED): "I am happy. It has been a fun week. I found the racing really hard because the standard is high and the girls are really good and that is what I enjoy. I like the pressure, the tight racing and my level coming up, getting punished for every mistake you are making. It is a bit of a shame that the racing ended the way it did because more racing would have been good."