Yes - it is one of those words like 'condescending' which do not mean exactly the same as we would mean by them. Elizabeth's manner is often rather disengaged from reality - for example, the way she does not see Mrs Clay in at all the same light as both Anne and Lady Russell do. She sees what she wants to see - a rather plain woman who is glad to be her friend and who would not have the looks or the wit to be scheming.