That's EXACTLY what it is... That is the spot that would hit the back of my head - in conjunction with the neoprene mask strap cover i have, it should make an occasional contact with it not matter... I rather have 100% side to side motion on the entire dive, and "possibly" hit my head on neoprene, then take that possibility away but NEVER feel comfortable when looking from side to side.... I also plan to ride the tank just a tad bit lower....