Actually, one has a lot more control that you can imagine. First of all,
the kites are 150 feet away from you and thus about 60 + feet up in the air
above the water. If you keep the handles level, the kites will pull
straight forward. If you pull left they turn left and so on. The distance
you pull determines the amount of variance from center that they will head
for. One actually has about 65 degrees from center to play in or an arch of
approximately 130 degrees to play with. Of course the more you cause the
kites to travel away from center, the less pull is generated because they
are spilling the wind force to maintain that heading.
So if you have a large body of water such as a lake, and the wind is blowing
straight across it, you could have a lot of fun. I don't recommend using 3
stacked kites unless you work up to this level but if you start with one
parafoil of say 6 to 8 feet and go from there. Consider the looks you would
get when you pass the power boats.
Don't think I want to try that with my kayak. The Carquinez Strait was
where I first tried out my beach umbrella for downwind 'sailing' - not
as
much power as a parafoil but easier to deploy and control.
http://206.40.48.186/uploads/UMBRELLA2.JPG