Check positions on video, not ball flight
The speaker recounts his own practice ratio: he would hit roughly a hundred balls into a net while reviewing them on video, then go outside and hit only a couple to see what the ball was actually doing. Ball-flight feedback mattered for very few of the balls he hit.
Channel: Todd Graves
Watch official source at 8:03Why this context matters
Memoir-framed description of how the speaker used to practice.