You've defined somewhat what IS is to you in terms of exercises, but, why do you need to do it? Why is it integral to aikido for you? Without the why, you can only blindly flail from what you are doing to why you are doing it. If you have a why as well, it helps you to work backwards and structure the what to make more sense - both ways. So... why?
Like I said, I wasn't trying to write a thesis on what IS is, that's another thread too, but I thought I kind of covered the why. You let people feel what you're doing and you show and explain why this way is better than that way. That's why I try to only touch on things that I can actually demonstrate to a degree that someone can feel and also explain in a clear manner. If someone feels it and doesn't care, not my problem, but when what you're doing fails to work on me or move me, don't fall back on the ole bad uke bit. That's one of the aspects of that whole "honest training" thing. If you feel something better and you're too dishonest with yourself to care, again, not my problem. All I can do is make the best of what I've got and do everything I can to improve myself and the people I practice with. I don't call myself a teacher of anything and I know that what I'm doing isn't high level. It's little more than a sample of some of the core skills and conditioning that make up IS. I don't even consider it aiki, but again, it's definitely some of things you need to make aiki and that's a step in the right direction. Especially when it's so easy to feel the difference.