I once saw a video where the rider uses a really old, unbattened sail for foiling.
Currently I use Goya sails of the newest generations. For foiling in light winds I'm trimming them with minimal loose leech to get maximum power. My biggest sail is a 2018 7.2 Mark with a 460 mast. My next sail down is a 6.3 Fringe with a 430 mast.
I would love to get rid of the big rigg but keep the power of the 7.2.
Now I wonder if the old sails of the 80s or early 90s had more power per squaremeter than the modern cuts.
Due to a missing loose leech and full profiles up to the top they lack controll but that doesn't matter for foiling .
If so, I could get a an old sail of 6.0 to 6.5 for a few bucks and rigg it on my 430 mast for really light wind.
Any thoughts?
Alex

Example following