Interesting (maybe) point...we did some research on height of contact and serve speed for our programme (wheelies) and with a rough contact point of 2m high, the maximum speed, with no spin, to keep the ball in was 84mph. The best servers in our sport hit 100-110, so they have some serious spin on their "flat" serves.
My point is that most rec players think "flat" or first serve means no spin, which is entirely not true!
Don't be upset by the results you didn't get from the work you didn't do...
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