Second Serve and the 20–30 cm toss

Field notes

The suggested recording setup is unusually concrete: put a phone 2–3 m high behind the baseline or beside the court, and record between one minute and two hours. A displayed example is labeled as an 18-minute session with 112 shots at NTRP 3.5; its feedback includes contact timing, serve-toss position, and split-step timing. These are examples on the page, not evidence of a completed customer analysis.