The four specific areas that we want to mobilize in the Olympic lifts are:
Ankle
Hip
Thoracic spine
Shoulder external rotation
A lifter that doesn't spend time mobilizing these areas could have problems executing the lifts with any semblance of good technique. A lack of mobility in these areas can lead to compensatory patterns that could cause injury.
The Shotgun Method allows you to train for both size and symmetry without having to skimp on either. It actually allows you to concentrate on the big lifts without neglecting isolation exercises that address lagging body parts.