Given the content just above, it seems more than necessary to reiterate some basic points, with some interpretations.
The Betz limit is 16/27. It applies in particular to wind turbines.
This is discussed on Betz limit and power available in the wind based on
The Betz limit applied to Airborne Wind Energy - ScienceDirect.
Highlights
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AWE drag power systems can harvest up to 16/27 of the power available in the wind.
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AWE lift power systems can harvest up to 4/27 of the power available in the wind.
In the abstract:
Another contribution is to show that Loyd’s lift power AWE devices during the reel-out phase can harvest up to 4/27 of usable power available in the wind, i.e. exactly 1/4 of the theoretical limit of the horizontal-axis turbines and AWE drag power systems with ideal airfoils.
So, AWE drag power systems [I would prefer rotary, and fly-gen (stationary or crosswind) systems, but it is another story] could reach the Betz limit, in theory.
Things are different for yo-yo (lift) reeling systems where the swept area is going downwind (is dragging) during reel-out power phase, at an idealized speed which is 1/3 wind speed. The power available in the wind is 4/27. And this is perfectly demonstrated in the publication in question. This can be easily verified by multiplying the force by reel-out speed, as shown here.
Note: as I repeat, a drag-based parachute or a parasail (with drag and lift) can cover the area swept by the “ideal airfoils” (which use lift during crosswind flight) with the same 4/27.
The parachute or rotor trains of SuperTurbine on a line capture a wind zone corresponding to that captured by all the units (before aerodynamic loss calculations): this does not affect the Betz limit in any way.
That covers the basic elements.
Now, on the specific case of a parachute with a drag coefficient Cd greater than 1 or 2 or a parasail with a drag coefficient Cd of 2.727 (and therefore a reel-out force greater than that of “ideal airfoils”), the 4/27 could be exceeded according to a simplistic and probably incomplete view I suggested. But that does not happen, at least because the Cd tends to decrease as the Reynolds number increases. See the values for a parasail. See also the low Cd of the gigantic Chinese 5000 m² parachute.
After all, one could design rigid kites or super-efficient blades that would also exceed the Betz limit (the real one, the 16/27 one): but this does not happen, because the Betz limit takes into account the open-disk actuator area. And it should be the same for the 4/27 in reel-out phase, regardless of the drag coefficient (if the Cd is higher than 1, the referenced area also increases, then including the parachute and its surroundings which increase).