No,

When singlehanding, the crew weight is not very important and under the (TRUE) formula rules of the F16 class you can have your mainsail cut adjusted to your weight (many do). The other two classes are "one size must fit all" and it simply doesn't work that way. In the end, the "stock" mainsail of the single supplier will favour one particular crew weight. And I seriously doubt whether the FX-one or I-17 mainsail is cut standard for 108 kg (240 lbs). I suspect it is cut rather for 75 or 80 kg. In effect he will always be looking for more power when his competition is nicely trapping along. In true formula classes this guy can order his boat without the stock sails and have a sail maker make him a custom sail that is optimal for his 108 kg weight. Is he still at an disadvantage relative to a 75 kg crew in say 6 knots, yes ! But less so then sailing at 108 with a mainsail optimized for a 75 kg crew.

Also people make far too much of some 20 kg weight difference. When you are in the top 5 of world then yes 20 kg will matter, but for the rest of us dummies it simply doesn't.

And if people believe it does then why don't they feel the same about 40 kg boat weight difference ?

Wouter