Take a classic KABAR, hang it on paracord and you have a neck knife. This is a ancient CARRY MODE, not some genius idea by contemporary knifemakers. They have set parameters of very small or skeletonised knives as this new idea to complement those $300 swords.
I've neck carried Moras and Puukkos for years . This is a 4" blade that I once forgot was on me, walked through a major shopping mall without confrontation or conflict until some girl from Helsinki got excited seeing it in California.
ANYTHING can break. Peter at Fallkniven has deliberately broken his fine blades in laboratory conditions.I have to work at getting mine dull, and he breaks them.
Vines are nasty work, one reason people use machetes and not neck knives.
"Respect the compromise"