From what I could tell, Nishio Sensei seemed to be explaining how to properly attack in Aikido practice, and not how to do Aikido atemi. I mean, I don't know how knowledge of how to do a proper shomen strike as he explained can be used in any way to facilitate technique, take uke's balance, etc. He does demonstrate atemi in an entering move for his shiho-nage, but he does little to explain how exactly to execute the atemi. Maybe I am misunderstanding, but when we speak of atemi in aikido, it is meant as what nage does in technique, correct?
I think Aikido atemi is unique to the martial art and isn't necessarily derived from any other art. The execution of atemi seems to come about when one adds "corners" to a round technique. It is not something like "do a kick here", or "do a punch here".
You are basically correct John but I disagree about it not being dirived from any other art... And Yes...There are other portions of the vids that better describe our Atemi which is basically taken directly from his experiance with Shindo Jinen-Ryu Karate, and Nihon Zendoku Iaido. Our Atemi are meant to finish the fight more than deflect or distract At least that is what some of his more Martial Senior Students like Tanaka Sensei would say. Other students of his follow the traditional line of "breaking balance" and actually practicing both is best.
Again as a disclaimer Those vids were produced about 18 years ago and some of our practice and approach has changed a bit since then to reflect the growth of other Martial Arts like BJJ. Our Aikido is always open to change and definately not static.
Back to the topic.