I have been adjusting my volley position for the drop shot, and things are a little better. However, I still think that what is happening needs maybe to be adjusted, as this is very difficult to avoid. Many times when even a soft strike is coming in, an attempted drop shot results in a hard-hit ball that goes way into the crowd (bounces off of them). The cause seems to be that the player is jumping or sliding into the strike. Here is another photo sequence showing this problem:
First showing how close I was to the incoming ball path prior to my having hit the drop shot buttons:

Next showing the first part of the jumping that results when I press the drop shot buttons:

Third showing the end of the jump, where you can see how far it put me out of the correct position:

Last showing the result of the strike:

I think that the jump in this case was unnecessary; I think that I was in the correct position for the drop shot when I pressed the buttons. I can't seem to make the game not do this. Well, sometimes it does it, sometimes it doesn't, and I am still trying to better position myself, but I am not sure that this is all my doing.
