My interpretation from reading others is that Landy really did this as an experiment, so we can all see if the L-foils are faster than the C's and J's. Plenty of discussion on SA, the cassettes are a few kg weight penalty. He also purposely wanted to push the rules, to see if the technical committee would ban them...
I don't think these are going to be faster round the track, you have to lift the weather board ala Hydros and Groupama. I haven't seen any other photos of the boat to know if there is a trick board upfucker setup to make that efficient.
All I really know is this is going to be exciting to watch! Krantz you're on-site???