Mr Bennet's words:

"They have none of them much to recommend them,... they are all silly and ignorant, like other girls; but Lizzy has something more of quickness than her sisters."

I think he may not mean this, that he is saying it to tease his wife. At the end of chapter 12, when Elizabeth & Jane return from their stay at Netherfiedl, the narrator tells us that

"their father, though very laconic in his expressions of pleasure, was really glad to see them; he had felt their importance in the family circle. The evening conversation, when they were all assembled, had lost much of its animation, and almost all its sense, by the absence of Jane and Elizabeth."