My first involvement with hull shape /design was with the Advance Model released in 1985. This was shaped from a 18' hull with the nose stretched out, and the aft hull sides flared out above the running surface, hence the "chine notch" found in every Advance. Perhaps the most complicated ski boat bottom out there is still the TBX, if you ever get the chance peek under the boat & look at that bottom, it was a laminators nightmare.