Re: Dobson and Arikawa Sensei
I remember in about 2000 or so spending a week in Tokyo to train daily at honbu dojo, and taking all of Arikawa sensei's classes. I got the impression he was a little different after about 5 seconds into the warm up which consisted of moving forwards and backwards doing shomen, yokomen cutting movement and tsuki, plus some taisabaki (alone). Now I get an idea what he was doing. Anyway, when uke was asked to attack him, the difference was as vast as the sea - it truly looked as though uke was afraid for his life. And yet the technique was always gentle, any sudden moves to demonstrate strikes, or limb manipulations were done sliding off uke if necessary, and when I took ukemi for sensei his touch was so light that I could adjust in his grip for the position - it was like having my arm surrounded by two steel loops attached to a solid machine.
I remember Arikawa sensei twiddling his thumbs constantly, hands placed one palm over the other at his hara, or behind his back like an old Chinese :-) When we were at the railway station (in Hiroshima IIRC) he would walk up to some of his students and remonstrate them for standing with their hands in their pockets, they ought to do what he was doing for their martial training and well-being. He was the teacher I would most have liked to train with regularly at Honbu. I shall miss him a lot.