Thanks for that FAA legal council interpretation reference
selfin. I had not seen that one before. I guess black of night
could indeed be counted legitimately, so long as it was subjectively determined by the PIC that reference to instruments was required in order to control the aircraft absent adequate visual reference. If I ever log instrument time for that reason, I'll be sure to explain my reasoning in the comments block.
I know I myself have certainly had to fly strictly by instrument reference in what passes for VMC on many occasions. Live and learn!