Due to the limitations of the information, the only eligibility criterion that can be used is the player's primary club, i.e. the club he plays most for.
From there, a few other things were done:
(1) Huntingdon & Peterborough was merged within Cambridgeshire
(2) Bristol & District was split into Somerset and Gloucestershire
(3) London was split into the various counties that surround it
The first question that interested me was the issue of "What constitutes a Minor county".
The following table shows:
(Blue) Counties that played in the National Open in 2011/12
(Yellow) Counties that played in the National Minor in 2011/12

Clearly from this data, it's obvious that Essex and Hertfordshire, the two SCCU qualifiers, are far larger than the counties from other Unions in the same competition. So is the other SCCU county, Kent, who qualified from the same competition.
I next looked at players who are > 160, which are the sort of players who would make up a Minor team, on account of needing to be an average of about 180.

This shows much the same pattern: The SCCU counties are far larger than counties in the rest of the country. In fact, they have twice as many 160+ players as the next Minor qualifier, Cambridgeshire. This makes it increasingly likely that they should win the Minor, on account of having a larger pool of players to select their team from.
I guess the question arising from this information, which I present without comment, is whether or not the current definition for Minor counties is a fair one? If not, how can it be improved?