Denmark Aarhus Unwashed and somewhat slightly dazed...
p. 13 of the rules Something like "If there is a disagreement concerning line of sight, roll a 20 sided die and the player with the higher number is correct." This is not verbatim.
No matter who invented random resolution of rules conflicts, it was still cool of the HS design team to add it! And btw, line of sight issues are just about the only thing that that can cause that kind of trouble in Heroscape,(as opposed to regular tabletop games) in my oppinion one of the things that makes this game beautiful!