Odd......knowing many pilots who put in 1000-1400 hour Years wearing helmets and body armor....not one complaint about Neck injuries. Piles, bad backs from Bell Helicopter Seats, and drinking habits but no neck injuries.
Adding a balance weight to the battery pack so the NVG's are balanced and no bending strain is generated goes a long way towards eliminating pressure on the Neck. After all, we do not pull the G's in Public Transport work as do Fighter Pilots wearing the things.