Bellow 6 knots, I'm sure you can find high aspect kites with more low end (Ex. Flysurfer 21m).
It can be misleading if the water is much colder than the air. It that situation you can have almost no wind at water level but 10 knots at 75 feet.
But on Dimitri's video, the kite is parked 25 feet above water. So probably same wind than at ground level.
Conclusion : let's stick with what we can see, feel and measure with an anemometer at arm lenght in an open area.
So what's the point? The point is that medium aspect inflatable lightwind kites can :
- turn much faster than high aspect kites
- water relaunch in almost now wind (3-4 knots)
- have great pop
- be cost effective
Most of the things I agree with your opinions
But I think there is a flaw in your statement when you say
"no wind at water level but 10 knots at 75 feet. But on Dimitri's video, the kite is parked 25 feet above water.
So probably same wind than at ground level"
How that would be the same when it's parked higher at 25 feet above water,
since there is a gradual increase in wind velocity with increased hight in blocked wind shadowed area
similar where I'm launching & landing over 10 years
The other flaw if it is flaw when you say "water relaunch in almost now wind (3-4 knots)"
Personally I've been flying my 21 Speed3 almost 2 years and I know I can't relaunch in that.
But since you're talking about medium aspect inflatable lightwind kite,
I test flown the 17m Strutless Cloud recently and I was needed at least 5 - 6 knots for relaunch.
Is it my limited experience with that lightest inflatable,
or would tell us how and which kite would relaunch in 3 - 4 knots because enquiring mind wants to know