The difficulties with adjustable dihedral would apply to any model. Overcoming the same stresses would seem to apply to any ornithopter design, since that also involves a changing dihedral. For a "fixed", but adjustable, dihedral, one approach would be to use a strut (or two) to hold the selected dihedral in place. Alternately, you could use a meshed "gear" at the rotating point that could be locked in place somehow. An interesting thought.
ian