Is it possible that a single sword blow?

I suppose it depend son the strength of the swords man and type of sword and the physic of the victim. Its well known that in the middle ages executioners could decapitate victims with a single blow of an axe, since the torso has more flesh to cut through it would take considerable strength to wield a sword with enough energy to slice through the entire body.

Yes. During the samurai days, a katana was not deemed ready for combat until it was able to slice a man in half with a single blow. Back then, they would test out the new blade on captured enemies/prisoners. Now they do it on pig carcasses. Look up Miyamoto Musashi. Considered by many to be the greatest swordsman of all time.

Through the average American, highly unlikely.

Through the average Scotsman, very likely (full of hot air)

Through the average Englishman ? Never. Made of sterner stuff :-)

Yes. I've seen them do just that to a pig carcass on Deadliest Warrior.

Yep. The Samurai Warriors could do this.