Here are three shots of Nat Young, ranging from 1968 to 1970. We can clearly see the transition from a super parallel deep V at the top, to a more moderated stubby outline in the middle, to a super short, pulled-in nose shape at the bottom.
All 3 boards featured the deep hull that was common in the early days of the short board revolution. All three were easily buried to the nose in a bottom turn.
The top board was serviceable, but no doubt sticky and hard to control due to the straight outline. The bottom board, with it's pulled-in nose combined with the deep hull, is "all drag and no go." Without any nose area to drive off of, the board sinks too far into a turn, and relies entirely on the fin to delivery any torque.
The middle board, however, seemed to have a right mix of outline and hull depth.
It's clear that the original shortboard hull designers overshot the mark. The next-gen builders (Liddle, Frye, etc) reigned us back in.