I`d always thought that heavier sailors have better power to drag ratio and hence better top speed; point of sailing would have little effect if it were case.
(For example at 30 knots a 100k guy might have say 10% more drag than his 80k counterpart but his 25% extra weight translates (all things being equal) to being able to genarate 25% more power.
25% more power and only 10% more drag would give higher top speed. Hence why Whity (when well powwered up) will always beat Harty for Vmax. Its why weight jackets work. The extra weight does not lead to a proportional increase in drag.A bit more drag but a lot more power. (IF (If If IF:@) the exta weight can still get up onto the plane.