Of course Mad King Ludwig should have been
accepted--it's uniquely identifying, good enough for me (as a
sidenote, that question occurred in a game against me).
Another example would be the Harold II question. I buzzed
in after the words "brother Tostig" and said "Harold
Godwinson." It is my understanding that they are one and the
same. Of course, if Harold I was also "Harold
Godwinson" then I should have been prompted; which I was
not. It is the responsibility of the question writer
to include all legitimate alternate answers (by
legitimate I mean uniquely identifying and not something
silly like giving the Norwegian name for The Man Who
Died (which was written in English) or
something.
This game is supposed to reward knowledge, not
clairvoyance on the part of the players.
My 2
cents,
Nathan Freeburg