Some more developments on my serving:
1. I found that instead of just bending the knees they should be "kicked out"! Its hard to explain, but basically instead of worrying about compressing the legs I'm throwing the knees out in front on the swing back from the initial weight transfer to the rear foot (from front).
It looks like a person slips on some ice where the legs are sliding forward leaving the body falling, only here its not the feet but the knees.
This component didn't so much add the pace to my serves as made it more fluid and consistent.
2. This one has really added some smooth violence to my serve - I noticed from my vids (
http://www.youtube.com/watch?v=2Tz_vhrWJRs ) that I was flicking my left hand downwards and not getting the tuck-in bend of the arm until well into shoulder rotation - so my left arm was getting in the way of rotation - so instead, I worked on keeping the palm open after the toss and bringing it in right before shoulder rotation is to begin, so this way that motion would add to it.
The funny thing is I noticed Pete Sampras doing the same thing as I was with almost no arm fold in and a flick of the hand down right before serving :shock: !
http://www.youtube.com/watch?v=9W1egSm1Kwg&feature=related
You can see how his rotation stops short because of it.
Compare that to Roddik's aggressive arm-fold BEFORE the rotation begins
http://www.youtube.com/watch?v=muKDqiVer0k&feature=related
http://www.youtube.com/watch?v=TAB7LpXi6_8&feature=related
Did I just find Roddik's secret ingredient to his not-so-secret weapon?