Come on guys, there are plenty of other people working on this material for the past few years, or have attended various seminars. You all should be able to chime in and talk about this subject. Presumably, your bodies have changed to some degree as well and you should be able to comment on it. Additionally, others should have some idea of the theory behind your own IS practices.
but you are doing so well. we don't want to disrupt your progress.
i think i wrote about the dantien/hara somewhere on aikiweb. the training of hara/dantien movement required the breathing portion which Sigman mentioned. i see the hara/dantien as the initiator, accumulator and the controller of jin, manage by breath. so you have the three: jin, dantien/hara, and breath (kokyu). can't be internal without the three.