The swing path of the golf club during the back swing movement must immediately begin to
move inside the straight to the target line and continue on this
inwards path arc to the end of the back swing movement.
During the
down swing movement the swing path is simply reversed so that
at the precise moment the club head strikes the ball, the golf
club is back in the original address position before swinging back
to the inside of the body as the follow through movement is performed.