This always leads to a certain kind of high-powered, high strung, heavily stressed and expensive solution to speed under sail, because the most effective and least expensive way to increase speed, adding waterline length, is denied.
Catamarans inherently have large stresses in their structures.
The current crop of maxi-catamarans has cross beams whose weight equals or exceeds that of either of their hulls. Current state of materials science places a practical upper limit to this practice, this upper size limit being tested right now by the entrants to The Race . We've seen significant structural failures in all 4 of the big cats finished so far for The Race . Last year, Bruno Peyron revealed his opinion that 100-110 ft was an upper limit for this sort of boat. In truth, larger boats are possible.