Canting the hulls seems to be gaining some acceptance. The Nacra F18 has cant, as do some new (but not all) A class cats. The idea is not new, and was applied to a NZ design cat many years ago. Seewww.coolmobility.com.au/Yacht/LightBrigade.pdf
and "find" Sundancer. There is a good drawing of Sundancer. If anyone has time, the pdf is a pretty good read too.
If the best sailing angle for a cat has the windward hull just out of the water, and the best hydrodynamic profile for the hull is in a vertical (relative to the water) position then a canted hull has some logic to it. I suppose that assumes the designer intended the hull to be vertical in the water. Suppose then that the gain amounted to a mere 1% speed increase. In a 100 minute race that would put a canted hull one minute earlier across the line than other wise. I would even settle for one half of one percent.
If I was racing in the US, or anywhere there is a fleet of 17's I would be staying class legal, no problem. Sadly for me the nearest H17 is over 1,000 miles away. My emphasis is on good fast sailing, aided where I can by affordable (to me) technology or innovation. I don't mean to appear disrespectful to one-design.