Dan, I'd have a much easier time accepting the relevance of IS, if you ever approached any aikido topic as aikido, and didn't always try to turn it into a discussion about IS. I understand the limitations of the signal vs. noise analogy, in that it can be seen as too rigidly dualistic -- but to you, it's all IS and that's all we should be talking about. There are no boundaries, nothing's off limits to be turned into an IS discussion/proselytization, and to be honest, it seems to me that you don't have any genuine interest in aikido per se -- only as a vehicle to promote your views on IS. If I want to read IS discussions, I'll go find an IS website. Is IS relevant to aikido?
Well, to be honest, it appears to me that IS was such a big deal that it pretty much dominates Asian martial-arts discussions. Qi/ki/prana. Dantien/Hara. Jin/Kokyu/Shakti. Blending with an opponent and "becoming One" with him (Or blending your forces/ki with all things around you and "becoming One with the Universe"). Concentrating the qi/ki at the dantien/hara. Putting the mind in the dantien/hara (sinking the qi). Breathing exercises to develop the body. And so on. I.e., the point is that it is supposed to be an overwhelming criterion and if you understand that, a lot of O-Sensei's writings begin to make sense, as does Ikeda's, Saotome's, Tohei', Shioda's, etc., etc., fixation on ki in the training and techniques of Aikido. Is it different from what you call 'Aikido'? Probably. And aye, that's the rub.