As far as I could see, nobody wore any weight the days I was there. The wind was so steady that it would be a dubious advantage for me unless the wind got significantly stronger.
My best day I had 10kg.Probably don't need it because of the angle you can go.Really helps when its square.
I didn't have to wear a weight jacket. But as jimbob said I had 3kg and even though the wind was steady I could hold more sail up.