You all hit the nail on the head....these rarities will shift from positions occasionally when more is known about each back, beleve it or not even after over 100 years we are still learing something new everyday about the set...
....collectors skew raritity when chasing in correlation to value, but we have a general idea of the "rarities"....
Lee, "rarities" are thrown around alot....i like anything red hindy and up classified as rarity, and include the bb.....