His 5.4 m no cam sail looked a bit under downhauled to me.
5.4 is the best and most natural size sail for windsurfing - at least if you are able to stay off KFC and Maccas

I never use less than a 5m as they become seriously twitchy and rarely use bigger than 5.4m.
So much difference in low end power between the two and yet only 0.4m difference.
Many windsurfers got into the big is better thing a decade ago but in actual fact whilst you do gain in overall performance by using a 7m or bigger you massively reduce the fun factor.
A great video by the best sailor pound for pound of all time.