Re: "blocking" with japanese sword
Another point - also briefly brought up in the article linked above - is how much force such a block (whether with a jo, a sword, or a bokken) would actually transfer into the arms and hands. That force, in my opinion, is in a lot of cases the more likely point of failure. This is also why you see so many redirecting/deflecting "blocks" in swordsmanship.
I would say that any time you could see a jo in a horizontal position and block a downward striking bokken, you saw one of two things:
- the bokken strike was stopped along its intended path of action (usually at the point of contact with the jo).
- the bokken strike was not delivered very effectively/powerfully.
I have seen several practitioners attempt to do such "blocks" against shomengiri with a bokken - relying upon the idea that the rotation of the jo would stop it from being sliced in two (an opinion I too have never held) - however, I have always personally considered this an improper application of jo techniques like makiotoshi or makiuchiotoshi, etc. To do these techniques properly you don't block the bokken at all - you attack the sword at the source of its arch. When you do this, there's no blocking involved - making the downward motion of the bokken an aid and not a hindrance to your efforts.