Great point!!
i say anything factory cut should be on the main list including brown lenox, red hindu ect and even THE FACTORY CUT upside downs(like your engle)...
then a Subset- i vote anything NOT factory cut...
in scarcity..
cobb
Brown om
proof
Blank back
front ghost
obverse ghost
or something to this effect.....just playing around..
i doubt cobb was issued at all....so it could be classified here and put the cobb issue to rest
man im going to get a load of crap for this one!!!LOL