unless there is a problem with a design and Nick's boats don't have those problems, kayaks don't need rudders, it's a crutch. Best to learn to paddle without one.

Some kayaks are designed to have a rudder. Fact. A surf ski for instance would be nearly unpaddleable (is that a word?) without a rudder. The rudder is designed to balance the area in the forward half of the hull. It allows the tail to be loose for maximum control in waves. Most other race hulls also have rudders so the maximum effort can be put into straight-line speed. Corrective strokes for steering waste energy.

THAT SAID: The Guillemot S is NOT one of the above boats. It really shouldn't need a rudder. An adjustable skeg could be an option.