@RetiredF4: This was my thought too, the reasoning being that (as far as I'm aware) the best L/D is based upon the lifting surfaces best L/D for a given mass, and the extra drag incurred simply means more gravitational potential energy needs to be traded to attain best glide speed, thus a reduced pitch angle (and as you say, reduced glide distance), but otherwise the same AoA and glide speed is required.
@Captain Sand Dune: I considered this, but the effect could be to increase drag as a result of increased alpha, which may not necessarily mitigate the drag induced from the extra appendages despite the lower airspeed, resulting in a net increase in drag and further reduced glide distance as a result of the lower forward speed.
I wonder, because given a set drag of the fuselage, etc.. the only variable that can be optimized is the L/D of the lifting surfaces, whilst reducing speed alone is the only way to reduce induced drag from everything else (zero airspeed being ideal), but would then be sub-optimal for the lifting devices.
