If you go by pure kinetic energy to determine if anything will kill humanely, you will be forced to concede that no bow can kill. Only Ultra-Mag depleted uranium heat seeking slugs from a CIA operated drone will do the trick.
Funny, when flintlocks came out the deer suddenly stopped dying from arrows. And when caplocks came out, same for the flinters. And on and on until today. Eventually, deer will stop dying from car strikes when we all have our Tim Wilson Jetpacks!