That's a good question but difficult to answer since I don't really have a control side of the experiment to compare with. She's low 50s as a small 15 year old, so definitely not throwing smoke. I'll say that the few pitches she threw with backswing (after not having used it in ages) seemed a couple mph faster. I'm no pitcher, myself, but watching myself after observing it in her, I noticed I come through with my arms early also. When I tried to correct it to create some lag, it felt more whippy. That, and the disparity between her arm position and what I see from that of others got me going down this rabbit hole.There is a bottom line question to ask, does it affect her velocity? Or her control?