[1][2] Herreshoff had designed winning America's Cup yachts which fully exploited the Seawanhaka rule, which was based only on a yacht's upright waterline length and sail area, to create narrow boats with long overhangs.
This reached its peak with Reliance, the defender of the 1903 America's Cup, which was described as a "racing freak", suitable only for certain conditions.
[5] Variables: The numerator contains a yacht's speed-giving elements, length and sail area, while the retarding quantity of displacement is in the denominator.
J-Class boats, for example, are any single masted craft with an R between 65 and 76 feet (adjusted upward from original to allow British yachts under the International Rule to compete.
Skene was the designer of J-Class yacht "Yankee" (1930)[citation needed], America's Cup contender, eliminated in the last selection match,[10] so had access to these rules.