I find neckers to be highly practical, but not in the scenarios that most others think. If I were to wear a neck knife it would be OUTSIDE the shirt, when concealment is NOT an issue - ie.- in the garden, hiking, etc. Neck knives if worn correctly, are placed in a most accessible spot for immediate availability. However, wearing it underneath a shirt, particularly where it is most concealable, defeats this concept entirely.
I am not advocating use of a knife for concealed carry or for self-defense purposes anyway ...
I have also become concerned about 2 other safety aspects of neck knives.
1) Already mentioned - the strangulation risk - this applies also to general outdoors use. I have had my neck knife snagged on branches etc. Doesn't have to be someone trying to do you harm.
2) Blunt trauma risk. A poorly designed / chosen neck knife can be too long, causing accidental trauma to your chest or abdomen in a fall, and the best-designed sheath can punch you painfully in the throat if you fall.
I realise I AM accident prone, but these are real risks. They've already happened to me. These days, to achieve the same effect, when hiking etc. I rig my "neck knife" upside down on the left side shoulder webbing of my backpack. I also find the "static cord" method to be useful. Jason.