Thanks for your reply.
Some of the techniques in the ogi chapter look amazing; on page 203, Shioda Sensei makes his uke (who is holding Sensei's belt) fall down; on page 205, he is lifted up on both sides and he manages to come down and causes both ukes to fall backwards. Do you practice these type of techniques in your dojo?
It appears that "ogi" comes from Daitoryu. In an interview, Kondo Katsuyaki Sensei
"In the traditional martial arts, a secret technique is usually taught at the very beginning... Daito-ryu also has a component called aiki no jutsu (fifty-three techniques) and they are truly wonderful. The aiki no jutsu techniques come after the 118 hiden mokuroku, and they are followed by the hiden ogi, the hiogi, the kaishaku soden, and finally the kaiden techniques. "
In this case, 'ogi' actually refer to specific techniques. The Encyclopedia of Aikido
has an entry for Hiden Ogi - "Transmission scroll of inner mysteries. The third level of techniques in the DAITO-RYU JUJUTSU curriculum covering 36 techniques."
However, I don't think "ogi" is mentioned so directly in the Aikikai or the Ki Society as it is in the Yoshinkan. Interesting...
Also, ogi or 「奥儀」can be translated as the "heart of the matter". So, the discussion by Shioda Sensei actually lays out the important principles of Aikido, which then manifest themselves in the techniques that he demonstrates in this section of his book. If you look at it that way, xuzen is correct - ogi permeates all your moves.