[Retros] How many times could a Diagram be repeated during aproofgame?

[A J Mestel]

As I understand it, we're defining a position as "different" if different
moves are available to each side, even though logically in a game having
the extra option to castle shouldn't prevent one side from claiming a 
draw if it wants to.

Yet, unless I've missed something, we are defining two positions as the 
same even if one is winning but the second is not because of the 50 moves 
rule!

We could argue that a position with 50moves left is different from one 
with 47 moves left is different from one with 2 moves left...

Or does this way lie madness?

      Jonathan