I believe the first grade given after two years training may have been 5th dan, nevertheless an impressive promotion. This included spending 6 months of full time training with O'Sensei, and when he was leaving the organisation to join the military. I think his elevation had a lot to do with his understanding of the 'ki' principles. The 10th dan promotion was in 1969, 29 years after he first started with O'Sensei, and I presume when O'Sensei realised he was not long for this earth. :asian:Koichi Tohei recieved his 7th Dan with only 2 years of training and was promoted to 10th Dan with less than 5 years of training. Why? Who knows, maybe O'Sensei liked him.