How do splayed wingtips work?
Splayed wing tips are like .... Fowler flaps.  Totally useless for cruising flight unless .... you want to try the "coffin corner" at perhaps 60-70,000 feet.  The best wing for cruising remains the high aspect albatross style.  However, they may wish to fold them back in cruising flight.
The writer had imagined this for the Etrich Taube.  Unfolding them on approach would greatly reduce the probability of tip stall and make lots of drag.  Strictly a low speed gimmick.  (By the way, slats also do this very well, actually helping high AOA pitch control).

However, the design does hold some interesting concepts:  no vertical stabilizer AND a high wing mount.  Sort of a fuselage mounted on a flying wing with an Hstab for better control. 
These concepts, along with engine mount location, bear further study.  The rest is for the birds.