physiologically someone with a long neck will be at a disadvantage to getting knocked out due to the torque that can be placed on it from external forces, as well as the ease to which one can connect to the sweet juicy chin. Strengthening the neck muscles won't matter too much, and that even applies to those with short stout necks. At least with a shorter more compact neck it makes it a harder target to hit, and the angles for penetration have to be tighter, faster, and sharper to connect perfectly the shake the cortex in order to relax the body.
it doesn't take a whole lot of force to make one dream, but what seems to be most important is the shape and size of the skull in relation to the body, and how hydrated the individual is at the time of the violent encounter. Healthy nerve connections for the youth make it harder to allow the mind to shutdown, but with each battle of chaos the damage and disintegration of the quality of the succulent mind begins to lead to easy knockouts in veteran fighters.
It's very traumatic to see a KO in real life, but after awhile there is something fascinating about it. The relaxation of it all.......I've always helped the fallen get back on their feet.
neck muscles are far more important in Jiu Jitsu where some people have different pathways of arteries and veins coursing through to their juices of knowledge. These individuals make it harder to submit via choking. They are tricky.....I have studied them a great deal...