Well, the pro's of the yoshinkan kamae might be the development of centerline, balance, and forward focus in training, as well as learning to focus your power, so that shite/uke learns how to concentrate all of their attributes on a given point. It is a training stance, and as such, is concerned with things of this nature.
The hanmi you see elsewhere is often concerned about protecting the deshi's centerline, and perhaps setting up irimi, as well as being a more neutral non-aggressive stance.
I think. Is that any clearer?