If you have issues with your lower body, particularly your ankles (overhead deep-squat test), your pelvis will thrust forward on the downswing and move into the space where the club was supposed to travel. The club gets stuck behind the body, and this leads to blocked and hooked shots.
The Fix
Hold the pole, get into a half-lunge position and bend your trailing knee as far as you can while your heels stay on the ground. Switch legs.
Sit on a physio ball and lift your toes to the left and right like a windshield wiper while keeping your heels on the ground and your knees still.
While sitting on a physio ball, roll your feet in and out in a pronated and supinated movement while preventing your hips and knees from moving. If you need to, you can hold your knees to keep them still as you do this exercise.