Flatter rocker boards are faster and have more stability as there is more area of surfboard in the water. This can help beginners or more competent surfers by using wave positioning to extract drive and flow to get maximum speed from the wave. This means surfing with less speed but with more radical turning ability. If you are surfing slow or fat waves a board with higher rocker will not perform very well. Crafting combinations of rockers is the shapers most secretive and skillful art.
Most shapers have their own combinations which have been tried and tested over many years.
Most shapers are using variations of this general concept in their all round boards making them work well in all conditions. Big wave rockers are a specialty art and the bigger the waves the less you have to generate speed. Increased tail kick helps maintain control and stability on bigger waves. SPSD is fortunate to have many respected big wave gun shapers on board. The Pin tail are best suited for big wave boards, they are the fastest tail shape and are the recognised answer to big wave surfing.