Some background on the arts of the Bujinkan
This originally started as a post on having belts in multiple arts. However, it became so Bujinkan heavy with my example, that I decided to place it as its own topic. I will create another post with my original thought, which was on the idea of having black belts in multiple arts over a short period of time. If you really don't care to discuss the Bujinkan, you can go to this post, instead. I left this intact since I think it can serve as a resource for other discussion on Bullshido.net. A large piece of this info comes from the book "An Introductory History to the Schools of the Bujinkan". It's a pretty well put together book, from an information standpoint, however, I believe it is overpriced for what it is. Also, it is technicallt twice as thick as it needs to be, since all pages are printed single sided. However, if you like to take notes, this can be useful.
My thought on this actually came while I was doing some reading on the Bujinkan, and it's partially relevent to this:
Soke Hatsumi is the grandmaster for 9 arts. And people usually howl about this, given his training consisted of weekend training with Takamatsu for 15 years (overlooking any practice that he did on his own). Now, prior to this training, he had studied Kendo, Karate, Aikido, Okinowan Karate, and held his 4th Dan in Judo. From this we can assume that he had good control of his body (due to his training) and was generally athletic.
Flash forward 15 years, and he is the master of 9 arts. However, if we look deeply into this we see something interesting. First let's look at the ninjutsu arts. Two of the arts Togakure and Komogakure, have very similar taijutsu (unarmed combat). Also, since the 1600s they were under the same family (Soke lineage). The only larde differences in them is that Togakure ryu had 18 Bujutsu (one of which was the taijutsu), most of which could be learned through traditional means. The other 17 were geography, disguises, meteorology, hiding (I guess this would be camoflague techniques), espionage, infiltration, strategy, gunpowder (firearm skills as far as I know), swimming, horsemanship, halberd, spear, sickle and chain, shuriken techniques, staff fighting, and swordmanship. (This list will be referenced later).
For Togakure ryu, there were three big things that made it different from the others: four-pointed shuriken, the shuko (hand clawsm and the bamboo breathing pole. Komogajure, had use of hook spears, a tree climbing tool, the use of headbutts and use of the head while fighting, use of armored sleeves while fighting, survival skills such as lighting fires in damp weather, and the use of double bloks and strikes.
The other ninjutsu, Gyokushin ryu specializes in koppojutsu, jutaijutsu, and kenjutsu. It also utelized sutemi throws, which are the throws that lit a persdon high and then drop them. An example of this that I can recall is a technique hat translated into "waterfall drop". Imagine "Morote Seoinage". Now imagine that when you took them over, you stayed more upright and moved their shoulder away from your body, countering the tucking action and the rotation of the legs that would allow for good ukemi that places them on their back. Essentially, they are now somewhat piked, and being driven head first toward the ground.
There are two Koppojutsu Ryu in the Bujinkan: Koto Ryu and Gikan Ryu. Koppojutsu is simply attacking and breakling bones. Here's a quick list of Koto vs Gikan, respectively:
-Short distace between opponents vs. larrger distance
-techniques are quick vs. techniques are more complicated
-Striking vs. loks and throws
-straight vs. circular
Koto ryu also has "techniques" of not telegraphine your techniques. I'm not versed on these techniques, but I'm pretty sure that most of us here are up on this idea, at least in theory, even if you are not good in practice.
The last four arts are Gyokko Ryu Kosshijutsu (Muscle attacks), Kukishinden Ryu Happo Hikenjutsu, Shindenfudo Ryu Dakentaijutsu (which also includes jutaijutsu), and Takagi Yoshin Ryu Jutaijutsu. (This is getting long, so forgive me if I gloss over this really quickly to reach the end.)
+Gyokko Ryu - Muscle attacks and knocking opponents off balance when striking and blocking, use of thumbs and fingers (boshiken)
+Shindenfudo - Kosshijutsu based (see Gyokko ryu), natural posture (the method in which you normally stand) in the dakentaijutsu, 5 postures for the jutaijutsu
+Kukishinden - Branched off from Kikishin. Use of spear and bo. Fighting on ships (postures are lower for better balance). Some weaponry that seems unconventional and not modern, but att the time were tools that were used in everyday sea work. 9 technique areas => strategy, short staff, long staff, naginata, short sword, blade throwing, spear fighting, and horsemanship. These 9 are different from the original 9. There is also some debate as to how Takamatsu came into possession of this art, and who it was originally passed on to.
+Takagi - Similar to Judo and Aikido, except there is focus on making breakfalling and escapes more difficult/impoossible. Emphasizes use of speed, and keeping the opponent close to you on throws, for defense indoors and in enclosed areas. This art was passed on to 4 people by Takamatsu.
If you paid attention to it all, you'll see that there is a hugh amount of overlap amongst the arts. Menkyo Kaiden in some of them would not require much more than learning additional techniques and theories on top of one of the other arts.