Select to expand quote
PeterP said..
But I also read somewhere that a heavier guy would be faster than a lighter guy on same size wing - so in the end it's all about technique and stamina anyways

Bigger guy on same wing= Higher wing loading (kg per cm2 of wing).
So all characteristic speeds (stall,best Lift/Drag,Max controllable) will be higher.
So in a simplified way a lighter guy will need a smaller wing to have the same perfo as a bigger guy on same design.
But at least in Paragliders and Hanggliders there is another factor due to Reynolds number (viscosity?) which means that for two pilots flying the same design at exactly the same wing loading the bigger guy+bigger wing will be more efficient and have better perfo.
But i do not know if this translates to a wing "flying" in water.