Biplane is known to deliver better lift to drag ratio compare to a monoplane. The most advanced modern airplanes (lowest transportation cost) are already built as biplane (see Russian replacement for the very world-best Soviet An-2). Larger commercial aircrafts are in conceptual development as biplane.
Indeed, the underlying specifics of the biplane aerodynamics may be washed out of an experienced windsurfer brain. In result we are observing a laughable execution of the idea from France followed by no so far ahead comments from, safe bet, USA.
3 wings can be more efficient compare to 2 wings if executed correctly. Infinite number of wings is ideal. Read Prandtl.
Remember, it takes a good engineer, not a surfer, to reduce these good ideas into practice.
From "Popular Mechanic" which I realise is not a peer reviewed journal, this suggests that you need both a good engineer AND a surfer to make an idea work. ( and if there is a bit of laughter involved then that's probably good for your health)
"Wind-tunnel experiments and mathematical analysis can only take you so far. Understanding all the dynamics of a jagged object cutting through the atmosphere is a bit like predicting the weather: There are so many variables, you can only extrapolate up to a point. So to figure out how a specific feature, like the shape of a wing, can be affected by the many stresses and conditions the open air will throw at it, researchers sometimes just have to build it, fly it, and find out. "
