Probably a good idea. As aimr75 says, it takes 5,000 repititions to learn a new stroke. As Ash Smith says, they have to be correct repititions. IMO, you're better off starting with hand fed or machine fed balls so that you don't have to focus as much on your footwork and movement and can just focus on technique. I also like shaddow swinging. But, I caution against shaddow swinging in front of a mirror which distracts your attention from what you are "feeling" which is all you have on the court.