I am too squeamish to slit and I use a pair of game loppers to chop the head.. no chance to become 'stumpy' and I can close my eyes when I do itThere are really good questions, and ones that I've wrestled with myself. I've tried that slit the throat and then stab the mouth method but haven't been successful. Even when restrained in a cone it was hard for me to hold the mouth open and still for the stabbing and I almost stabbed myself instead.
My guess is that the most humane method is instant decapitation. I say "guess" because I've yet to do this myself. I use the cone and slit the jugular because I can manage it completely by myself. I'm not convinced I could cut off their head by myself without removing my own hand in the process. Perhaps if I had a chicken guillotine...
Much of my butchering occurs when my husband isn't home, and my son is useless when it comes to killing anything. (He can't even bring himself to flush a sickly goldfish down the toilet if it's still alive.) The problem is, even though they bleed out really well, it can sometimes take a lot longer for them to die than I would like. I've found that the more hyper the bird just prior to putting it in the cone, the faster they die. For that reason, I grab the bird by the legs and allow it to "fight me" by flapping and 'doing crunches'. Then I quickly secure it in the cone and make the cut. The heart is still pumping so fast that the blood pours out quickly and death takes just a few minutes.
I've also put the birds into a tonic before culling my holding them upside down for a while until they grow calm and their eyes are closed. They stay very calm and still through the entire process and some haven't even responded to being cut, but death takes longer. That bothers me. I want it over quickly.
One word of advice...if you choose to cut the jugular and let them hang upside down (cone or rope, etc.), I suggest you walk away once you know you've cut deeply enough. It's just a lot easier to not have to watch them go through the death throws.

