Back in the day, shortboard hulls had DEAD STRAIGHT tail rocker. Transition era designers figured that since boards were so small -- which they were by longboard standards -- there was no need to generate any drag in the back half of the board for maneuverability. The result was super efficient planing hulls...but they were sticky as hell to turn! It only took a few years before a little bit of tail rocker crept into the standard shortboard.
--- Paul Gross