2 Part Technique - Holding the North/South position is often best accomplished with one-arm-over and one-arm-under, forming an Over/Under Control with your over-side hand ready to attack your opponent's neck. If he is blocking you from connecting your hands together to squeeze with the Gable Grip, keep heavy and clean up the impedance with your knee. If he's blocking too high for that, simply connect your hands with the Ball-N-Socket Grip (Marcelo's versatile choice for Seatbelt Control, his Guillotine Choke, and many other holds) and employ the Arm-In North South Choke. While drilling, open a dialogue up with your training partner to ensure that your finishing pressure is only attacking his throat and carotid arteries and not his chin, jaw, cheek, shoulder, collarbone, or anything else that gets in the way.