Nope. I did do some checking, and Shotokan seems to follow that pattern as well.
There is a published guideline for the JKA which would lead you to believe that. This is another one of those what is in the book and then what is there in real life situations. JKA-certified instructors vary on what they require in their own dojo, and indeed those are MINIMUM guidelines that represent a very aggressive promotion path. Anecdotally, I believe most take longer than 10 years, certainly the people I know did,
Is there a main aikido federation? If so, would you mind posting their time in grade requirements? I'll repeat: based on conversations with practitioners of other systems..... Take it for what it is: a post in an internet conversation, not a scholarly work; I think you got my general point.
I am a member of the USAF which is aligned with the Aikikai, headed by the Ueshiba family. These are the USAF requirements.
6th kyu - 20 practice days
5th kyu - 40 practice days after 6th kyu
4th kyu - 80 practice days after 5th kyu
3rd kyu - 100 practice days after 4th kyu
2nd kyu - 200 practice days after 3rd kyu
1st kyu - 300 practice days after 2nd kyu
1st dan - 300 practice days after 1st kyu
2nd dan - 600 practice days after 1st dan - not less than 2 years after shodan
3rd dan - 700 practice days after 2nd dan - not less than 3 years after nidan
These are officially recorded dojo attendance days. If I attended 2 different sessions in the same day, I'd still only get credit for one day. Also considering that most aikido dojo are not open 365 days a year you can see the difficulty in meeting those TIG requirements. Add to that the generally high standards in aikido where you are invited to test when you know the techniques rather than just ticking off the time....Well, I don't personally know anyone within my band of aikido training experience to my knowledge who made yondan very quickly.
I'll repeat: based on conversations with practitioners of other systems..... Take it for what it is: a post in an internet conversation, not a scholarly work; I think you got my general point.
I understand this is a stray internet conversation. Nonetheless, I don't think the statement was necessarily accurate so I wanted to speak up.