I think that it is meduyak from the Shulchan Aruch that he is understanding that the concern is that the majority of women are not suited for learning Gemara. Therefore a father should not require his daughters to learn the Oral Torah (beyond the halachos they need to know).
However for the minority who are suited for such study it is a wonderful thing if they learn the Oral Torah and if they come and ask to be taught (and you deem them capable and worthy) you should teach them.