Here's what I was thinking, in a bit more detail:
- A: Normal "box" tail - long wake, recirculation bubble helps drag
- B: The 'rear window cleaner' - adds drag but doesn't alter wake much - might cause the recirculation bubble to be unstable, as the 'window cleaning' flow is counter to the bubble rotation.
- C: The Frey and Flugel wings appear to be trying to fill the wake directly, with a small or no recirculation bubble
- D: What I was thinking - use the wing to stabilise / control the recirculation bubble, shortening it and bringing it closer to the 'ideal' / k-form shape
