John Fereira wrote:
...One thing that sea kayakers, even those that regularly paddle
what might be considered "intermediate" conditions, have to deal with more
than ww kayakers is the wind.

For that reason, most sea kayakers use feathered paddles.

I'm not sure how true that actually is. The use of unfeathered paddles
seems to have increased dramatically in the past few years.

(I'm not sure why most ww paddles are feathered at all)

It was originally done to help the paddle clear gates in whitewater
racing. Again, in the past few years, the trend in feather angles used
by whitewater paddlers has changed dramatically, with many using little
(10 degrees) or no feather now.

...so that when a
forward stroke is taken the out-of-water blade cuts through the air rather
than pushing it with each stroke. Otherwise, when paddling for several
hours in a strong wind, it can put quite a bit of pressure on the wrists.

Unfortunately, the common 45-75 degree angles used by sea kayakers cause
one blade to lift and the other to dive when paddling into headwinds and
with tailwinds. They also catch beam winds in the same inconsistent
manner. The stronger the wind, the harder these things are to control.
This can create significant stresses on the paddler, reducing the
benefit of reduced drag on the paddle from feathering.

In contrast, an unfeathered paddle has more drag, but it's consistent
and predictable.

Even with a feathered paddle and using good torso rotation rather than "arm
paddling" the cumulative effect of strong winds blowing on the blade can
have an effect after a long day.

Yup.