Re: Ikeda's videos, my video, your video. Kuzushi on contact.
I liked Daniel James' idea to explore/film the 'the making contact' aspect. I think starting from an static grab doesn't give you much to work with. Your partner is applying force, but there's no momentum to it. IMHO you must force or trick him to start moving in order to actually unbalance him ... maybe an atemi or just the threat of it. I know that this probably negates some of your goals, but might be worth trying as a starting point.