I was researching this and saw mixed answers from a person asking the same question in yahoo. http://answers.yahoo.com/question/index?qid=20080616122516AAcnHsU Really though, not a lot of people here like to play tennis or they are busy during the time I want to play. Therefore, I go to a wall a town over to play but now I am a bit cautious to play against a wall which may ruin my strokes. Im mainly using the wall to learn to use a 1HBH and BH slice. Yesterday, after transitioning from the wall to play against my friend, my 1HBH has improved but still very very inconsistent. But does playing against the wall really ruin your strokes? Also, is there a drill to work on volley without a person?