you are going to have to become well educated yourself about windmill pitching mechanics, & as Hillhouse would put it the difference between styles & absolutes. There are some parts of the pitching motion that are the same between all elite pitchers & you will need to learn them. The biggest asset for me was buying a good video camera & learning how to watch slo-mo video. These girls simply move too fast for a nonexpert to see the problems in motion. With time & slow mo video you can compare your DD to what you see in the elite pitchers.