The serve is a very frustrating beast. I think my first serve is a second serve. Both use a little knee bend, a little rotation, and spin. With that, I am pretty competitive at the 4.0 level, and the second serve is far better than the dinks of some 4.5s.
What will happen is that on Sundays when I am relaxed, the serve will be great. On Fridays, like today, I will be upset with the quality. On Tuesdays, it will be in between. I cannot get the rhythm the same all the time and I cannot tolerate it. I will serve one in the middle of the box and then walk away disgusted that it was not deep.
I don't feel the same every time I serve. One day I am very smooth all archy and heads up and knees bent, one day I am flat footed.
There must be a way out of this. There are 4 adult players in my club who serve better than me, and they are all 4.5s, and I know that all 4 have played since they were kids, two here and two in the Philippines. Which doesn't give me much confidence in learning anything from the rest of those around me. Out of the 4 teaching pros here, 2 of them have worse serves than me, one is the same as me, and the 4th one who can heat it up had beaten Vijay Amritraj. I have observed his serves very carefully, but his 6+ height gives him trajectories others don't have. So the pros are not useful either.