Well, I've been away long enough. Time to stir up the waters again [IMG]http://www.fightingarts.com/forums/ubb/smile.gif[/IMG]
I would say that "DO" is a very different animal to Jutsu. Obviously one is derived from the other but that doesn't mean the two things are the same. DO was, and is, a way to make something constructive out of something destructive. The technicalities in a DO art are more important than the result, in a jutsu art the converse is true.
The point of a DO art is to struggle with techniques that are difficult to perform, the point being that you emerge a better person for having persevered, not for having mastered the technique. Any fool can learn to fight, Jutsu isn't character building in the way a DO art is.
DO arts weren't simply introduced to fool the authorities into believing anything about MA's because the authorities were themselves trained in them!! The Samurai class became the administrators of the post fuedal era. Samurai ryuha found themselves with a problem, no-one had any need for their fighting skills any more. The sword had given way to firearms and modern western weapons so completely that the MA's had almost overnight become anachronistic. So, in the best traditions of business, the Classical MA's evolved and became something else, something people wanted.