Pretty happy with my serve since it's the best weapon in my arsenal. Now that I'm 60 it has slowed down a bit. I've also developed a serious rotator issue (from an old v'ball injury). However, by employing a generous knee bend (and other elements of a good kinetic chain), the shoulder/rotator issue does not hamper my serve very much. The only problem that I have with the serve is that my toss
sometimes "goes South" (becomes erratic) when I am fatigued or, more often, when I did not get a good night's sleep.
I first made significant strides with my serve in the mid-1980s by repeated viewings of Stan Smith on the SyberVision
Neuromuscular Training tape. I also learned quite a bit about using pronation
from playing badminton
in the 80s.
In the 1990s, I started studying slow-mo videos of Pete Sampras' serve mechanics. I adapted/modified his serve to suit me. This took my serve to a much higher level. I have since modified & improved my serve futher from viewing Pat Dougherty (the Serve Doctor) videos, Will Hamilton's serve sequences (FYB
), and slow motion videos of Federer, Sharapova and others.