: I see that most new sea kayaks over 15' offer a deployable skeg. I have just
: ordered plans for a Guillemot. Should I consider adding one to this
: design?

The Guillemot is known for being fairly loose tracking, which is great if
you like playing, especially in waves. On water where the wind hasn't much
fetch to build waves, but is blowing off a low shore line (to pick a
worst-case scenario), loose tracking boats can be very sensitive to trim.
Too much weight forward and the stern blows downwind (weathercocking, which
can be a pain). Too much weight aft and the bow blows downwind (lee-cocking
which is a whole lot worse and can make it so hard to paddle back into wind
that you risk being blown out to where it gets a lot more dangerous).

A well-balanced boat weathercocks slightly, and tracks well as it gets up to
speed, and if you are good at packing your boat, you may not need a skeg.
But very few boats are exactly wind-neutral at every angle to the wind and
at every speed, so most people who paddle in windy places like a weathercocking
boat and a retractable skeg. Err on the side of a bit too much weight packed
forward and the skeg can correct for that.

Note that designs that are intended to have a rudder are different boats from
those which aren't - they would weathercock very strongly without the rudder.
If you put a permanently deployed rudder on the back of a boat which was
designed to be wind neutral, the result will be severely lee cocking boat
which will carry you off downwind ...

I'd paddle a few boats which have skegs, with and without using the skeg (good
practice anyway, as they do jam occasionally...) in both windy conditions
and waves (both chop and swell) to see how you feel. Personally, I like
being able to just nudge the skeg a fraction down and have my angle to the
wind come round to just the right place without having to use correction
strokes or keep the boat on edge, so I have a skeg. But if the boat fits
really well (you wear it rather than sit in it) then holding an edge isn't
that hard. Having to take your hand off the paddle to adjust the skeg is
not for everyone, especially when the wind gets gusty ...

Andy