Re: Defining the word "Aiki" and looking at the phenomenon it describes.
Aiki, in my interpretation, is ANY movement to engage in the most natural and straightforwardest manner to absorb uke in the goal of making two bodies into one.
If the movement is not natural and the most straightforward (ie the blending does not come automatically, not most efficient way to go from point A to point B), this is not aiki. My theory is that because of these 2 factors, you can do the techniques with minimal or no contact. Aiki is automatic in the point of view of nage in terms of his blending if these 2 factors are present. Aiki is automatic in the point of view of uke as to his response to nage's intention whether or not the engagement by nage has commenced.
Aiki IMHO therefore is not concerned only with nage's control of his mind, body and spirit to unify these but also tries to control uke's mind, body and spirit to unify everything into one body. During the technique, there is no nage nor uke but just one body until uke is thrown. This is just my theory. My 0.0001 cents.