Something that can be done is getting a straight board with a smaller 45 degree tip down a cassette box if the cassette box is setup like the modern adjustible A Class style, with the addition of a small flap on the inside of the hull. A 12 degree incline + say 45 degrees gives very nearly the optimal board shape. Is the additional small end piece ( the bit that gives the vertical lift ) an end fence, not in my book.

I hope they leave this get out clause in there for future experiment with what is effectively L boards.