Upper Body Driven Tucks
End your starting position with your front knee behind your front hip, and, to move down the mound, you must stride.
Your body uses your throwing arm to offset your movement down the mound, and you delay your glove arm tuck until you complete your stride.
Your upper body works alone, and it’s impossible for you to know with any certainty where any single pitch will end up.
Full Body Driven Tucks
When you end your starting position with your front knee in line with your front shoulder, your glove arm tuck will spin your body into your stride and force you to end your stride with your hips and shoulders at opposing angles.
You use your entire body to relieve the tension between your hips/shoulders by making a throwing action that’ll repeatedly produce the results you want.
The Hitter’s perspective.
Let your glove arm tuck force an upper-body-only delivery, and your different release points/varied arm speeds risk tipping your pitches to the best-trained Hitters.
However, use your glove arm tuck to spin your body down the mound, and your Opponents see a fastball arm speed, must guess at ball speed/movement and have a much tougher time reaching base.
Need a more efficient starting position? Coach Skip is waiting for your call.