Re: Value of atemi
I would go one step further...than necessity to take him off balance...
It is not necessity to do it, but to possess the ability to do it, AND to make your opponent understand that you possess the ability is sometimes all that is necessary.
Then again, sometimes even if you don't have the ability, creating the perception that you do is all that is necessary.
Deception is a viable option that we have. however, we are talking tactically, and not necessarily philosophically.
Philosophically, I think atemi is important as a tool to teach us things. Without it, what we do is very limited.
The important thing about aikido over many other forms of budo is the concept of maŠi...that is the space that exsist between uke and nage. In BJJ we start with the assumption that the space is gone most of the time. In aikido we always pretty much start with that space present.
With that space presence, both uke and nage have a choice. Choice is an important part of what we are learning in aikido. We can make many choices which affect the outcome of an engagement between uke and nage.
Atemi provides relevance and importance to what happens in that space. Without atemi, bokken, jo...it becomes very limited what we can train physically with respect to choice.
As many philosophers have said, I cannot affect what others do to me, or the choices they make...I can only affect how I react. Atemi is a enabler of this process...it is an option (choice).
As with all choices, we need to be honest with both ourselves and our intentions. That is why it is important to have good atemi when practicing.