I suspect Burdick had at least a rough idea how complex the set really is. And rather than make it into three or 16 or more sets, he opted to put any card that seemed to be from the same set in that grouping.
If it's about this size, has white borders, and is on this sort of cardboard and has a brown caption then it's a T206.
Anything else is easy to categorize as its own set.
It's that way with a lot of large complex groups of related sets.
The old Judges
And the M-101s
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