The first wave of shortboards were haunted by the dramatic decrease in paddling...as compared to the recently deceased longboard era. Shapers responded with the concept of the tail being the thickest part of the board.
Above are two representative examples. The "reverse foil" of the nose-to-tail profile led to some lousy hydrodynamics.
It wasn't long before thicknesses moved forward, tails thinned out, and "real" shortboards were born...
