Long video but pretty interesting. Removable wing sections make the wing smaller. Pretty simple- surprised no one thought of it before. (Actually Multisail in windsurfing did this sort of thing many years ago, but it never caught on. I think part of the problem was you almost had to re-rig the sail and maybe the sail design itself wasn't that good.) In this you simple unzip the back of the panel and the wing drops about a meter and becomes a Batwing. 
This is all part of the X-15 One Design racing class that Starboard is now promoting.
Discussion of reefing is about 2:45 and impact on performance at 19:45
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What happens in a black hole stays in a black hole.
The "luff sleeve" at 12:00 is just as interesting. I love his explanation of his first time with the reef: I was overpowered and instead of pumping up a smaller wing, I just got out a pair of scissors...
I think you are seeing one of the possible replacements for kiting in the Olympics. Formula kites and their expense did kiting no favors as an Olympic class (imho).
She did well at Defi Wing, taking the women's overall. Good for her. First time an American has ever won a Defi event.
https://freewing.world/fiona-wylde-wins-2024-defi-wing-on-air-team/
Yeah the use of scissors as a tuning tool got my attention too. It got me looking side eyed at one of my wings. Sewing zippers is pretty hard but a multi size wing seems like a pretty good idea... I think it is an idea that will catch on.
What happens in a black hole stays in a black hole.