Are you striking the ball on the heel?
A massive percentage of amateur slices are not caused by swing mechanics at all, but by the physical law of gear effect occurring on off-center heel strikes. Modern driver heads are engineered with a curved horizontal face (bulge radius). Because the clubhead rotates around its center of gravity at impact, striking the golf ball just 0.5 inches toward the heel causes the clubhead to twist counter-clockwise. By Newton's third law of rotational momentum, this face twist forces the golf ball to roll clockwise across the face like meshed gears, imparting 400 to 700 RPM of violent clockwise slice spin—even if your swing path and clubface were perfectly square.
When you speak with a coach, ask this simple question before you pay: "How do you measure my horizontal impact location across the driver face?" A real PGA craftsman sprays dry impact indicator (or foot powder) onto your driver face during your very first warmup bucket. If the ball marks cluster inside the sweet spot near the hosel, the coach diagnoses the physical cause—often a driver shaft that is 0.5 to 1.0 inch too long for your wrist-to-floor measurement, causing heel contact that no swing thought can fix.
Trimming an excessively long driver shaft by half an inch centers your strike pattern on the sweet spot overnight. The instant your strikes move from the heel to the center of gravity, gear effect disappears—and that phantom slice that haunted you for years vanishes with it.
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