As my final point, I'd like to say that your conception of aiki is obviously very different than mine. Excuse my French, but why do I give a shit if I can put "aiki" in the tip of my sword? Swords are amongst the most unforgiving handheld weapons man ever created. One rarely gets more than two brief instances of contact before one or both of the combatants are mortally wounded. The first contact almost always wins. And that contact is more likely to be sword on flesh than sword on sword. Real skill with the sword must be a skill precedes physical contact. It must. If your conception of aiki doesn't account for this, then I very seriously doubt it is in accord with Morihei Ueshiba's conception of aiki.
Well if you want to go the waza route with swords: extraordinarily effective kiri-otoshi or suri-age. If you are executing other waza, the ability to off balance and create openings by returning the opponents input energy back into them would seem to be inline with conventional aikido thought.
No different from "aiki" (IP) in any other context.