The explanation is that you need to balance out centrifugal force F=mv^2/r. "Sharp turn" has smaller radius, therefore much larger the force. By turning in the

The explanation is that you need to balance out centrifugal force F=mv^2/r. "Sharp turn" has smaller radius, therefore much larger the force. By turning in the opposite direction first, you're making the turn much less sharp, increasing the radius and thus reducing the force.