
.
interesting idea.
Actually a standard chrome dome works quite well in the wind if you are willing to learn how to "fly" it.
Tip the leading edge about 10 degrees below the angle of the prevailing wind and the umbrella will create lift and become more stable.
This is why i never try to afix my umbrella to my pack.
Changing the angle of attack and being able to duck branches or doff the works for wind gusts makes the umbrella much more workable as a solution.
I am not convinced a "floppy" solution is any better than active control.
Interesting none the less.
Umbrellas are much maligned and undeservedly so by those unwilling to learn how to use them properly.
They require an active approach but can be used even in highh winds succesfully.
in fact, one of their greatest uses is to deflect high winds.