My guess is virtually all neck injuries in the sport venue are the result of decoy error. Jamming the dog by catching him wrong. Decoys are very important in sport work. When you say catch the dog, that is literally what you are doing, giving the dog a target and having that target be soft- moving away from the dog, not towards it, as it leaps for the bite.
I think in a law enforcement application, the dog is rarely taking a high flying bite at a bad guy who is facing them like a decoy would do in sport. The bad guy is either running away, and the dog will grab the closest thing to him, or the bad guy is hiding and the dog goes in and grabs the closest thing to him. Law enforcement isn't giving points on a nice arm bite, they just want the dog to bite and hold on. Same goes for a personal protection situation. There is NEVER a reason for a personal protection dog to be sent after someone who is either running away or even running towards you. PP stuff is a lot more close range- bad guy grabs handler, dog bites. Bad guy breaks into house, dog bites. All stuff that is close range biting and the dog will rarely be moving at top speed over a distance.