IMHO, you are barking up the wrong tree.
The benefits from working to optimize her motion aren't worth the time. From here on out, she should work on control, movement, increasing speed and changing speeds.
Her progress is going to depend more upon her pitching coach and her own interest and desire in becoming a better pitcher. About the only thing a dad can do at this point is catch her.
This strikes me as one of the most accurate statements I have read in my years of lurking on this forum. At what point is trying to change my DD's pitching "style" counter productive. It seems to me to see that the best pitchers in the Model Pitchers thread all hit the same basic absolutes ( IR, leap and drag etc.) but do not necessarily have the same style. For example half of the top level pitchers I have observed swim their glove arm. At what point would it be better to focus on the things suggested by Sluggers. I think at 15 my DD has hit that benchmark.