I think you've really hit the heart of the matter. DL's official descriptions, at least so far, are all about having designed a "best in class" overall program--- meaning some kind of measure of "average" benefit offerings across all levels from general member to top tier.

They appear not to understand so well, however, that each individual has a fairly set particular pattern of flying and is concerned mainly with his/her marginal benefits level, as compared to the alternatives of competitors. Being "number one" on average does little good if the folks at the top tier(s) perceive they might be better off somewhere else. Arguing "but we're the best, as a whole program" rings rather hollow, to those flyers..