| As stated
Many shows do in fact have a Male Champion award. Also as mentioned, Males have an advantage in smalle sizes not only because they tend to "finish" earlier (and at smaller sizes than females), but also because body shape, although important doesn't typically start to differentiate between sexes until around the 18" range (give or take).
As for "duel standards" for judging? Let's see, for a large show tih say 200+ Koi here in the US, there would typically be 16 classifications and 8 sizes making for 128 "initial competitions" (let alone best in size champions, between 2 sizes) and the top awards. Now that process takes anywhere from 3 to 5 hours depending on individual factors. By having duel standards, the competition is "diluted" and now there are 256 "initial competitions" and judging becomes a weekend afair instead of a few hours....unless even more judges are added at a larger expense to the hosting club.
But hey, clubs are free to set up the show in a manner that the prefer too.
Steve |