Depending on what you are training (no it's -not- all the same) Moving and fighting with IP/aiki can be more...or less...automatic in nature. There are methods that completely change the way the outside moves from within in certain patterns of movement. These patterns become natural. It is this combination of the inside moving the outside that the masters talked about. This is the heart of what I refer to about freestyle effecting kata. not only is the force-of say a grab- nuetralized complelety, certain secondary actions from your natural movemnt can, make the uke respond, sometimes in dramatac ways. On another level there is a pronounced tendency to stick and control at any point of contact. Were your body to move in certain ways virtually all of these points of contact can act as capture and motivational points on their centers and can lead to any manner of throws, and or entry points to do some seriusly damaging and repetative hits, where the body still maintains contact to once again control and then again to set up a series of hits. Other methods of movement really cannot accomplish that they deal with power differently.
This ties in wiith your comments here:
Not all of the methods for IP/aiki will tie in to Japanese arts and weapons in the same way. Some of the teachers out there training with different sources are forming their own opinions based on observation, explanation and feel.
Hmm....note my compliments on them and you see how I feel.
Could you cite some example(s) of other methods of IP/aiki that you feel do not accomplish these ends, and what exactly the main failing point is with them that makes it so? I'm not asking for an essay, but I'm just curious as to what you see as the main stumbling blocks there that would lead people astray.