John,
That's a very interesting suggestion. Basically what you are suggesting
is a way to compress this database.
And in fact just **attempting** to compress this database would teach us
a lot. For example:
as i was reading these posts, it occurred to me that there are many
positions in go that are equivalent. for example, if a group has two eyes
and big eye, white could have a variable number of stones inside. these
positions would be all equivalent in some sense. i was wondering if that
would partition the set of board positions into a smaller set of
equivalence classes?