I had a cat when I was a kid. Whiskers was his name because he had...well, really long whiskers. Leave me alone. I was 6 when I named him and we probably still had lead painted walls. Anyway, Whiskers was this chonk of monster. Close to 20lbs and built more like a lion than a house cat. However, if you put anything across his back: a sock, a glove, a string, anything...he would bottom out his belly to the floor when he walked away and act like you just stacked 5 bricks on top of him.
...that's how I feel about neck knives. I just can't find one that is remotely comfortable enough for EDC. I do have a Spyderco ARK that I wear to the beach from time to time. However if I am hiking or walking or working...nah, something even a bit heavy and either tucked in my shirt where I can't get to it or flopping around isn't my jam.