Not to change the topic, but why do you say such a thing that it was such an "awful way to die"? Seems to me it's probably pretty quick. A quick slice and off comes the head. With the brain severed from the body so quickly there probably was no time to feel any pain. Those Japanese officers were probably pretty good in weilding their blades.
As for an awful death, I'd say the Chinese "death of a thousand cuts" would be pretty bad. From what I've read it took awhile and the person was given herbs to heighten the pain. If I had a choice, I'd go for the head lopping.
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