In competitive sailing we are looking for every advantage we may get if we want to win and going fast is a pretty important advantage to have - the gains from using the correct sails are more than just marginal!.
Not too long ago in a lot of classes crews could be seen visibly relaxing as the kite went up, and the procession began. Happily now in all racing we understand how to make gains and use the downwind to our advantage.
There are a lot of theories of why we need sail twist. They are mainly disputable, but the fact is that boats go better with twist. That’s all we need to know to understand the importance of this factor of sail trim. For us its simple to prove - when the tell tales are flying, and most importantly at the head the leech tell tales,