In ch.33, Elizabeth is thinking about what Col. Fitzwilliam has just told her about Darcy breaking up Bingley's romance because there were objections to the lady.
"To Jane herself," she exclaimed, "there could be no possibility of objection; all loveliness and goodness as she is! Her understanding excellent, her mind improved, and her manners captivating.
Obviously, JA meant something specific by an "improved" mind, but what exactly, since I would have thought that "improved mind" and "excellent understanding" meant the same thing! Also, this phrase just reminds me a little too much of a real estate agent listing the advantages of a particular house: "spacious grounds, newly renovated bathroom", etc.!