A big shift began for me when I studied Feldenkrais and he (his Method and writings) directed my attention toward smaller and smaller movements until I noticed a place between thought and movement where everything begins.
Just to clarify again, I'm not saying Feldenkrais teaches IP/IS.
To me, Feldenkrais is like WD40 for the mind/body connection.
It allows you to become more and more subtly aware of the mind's access to the body.
If you're a dancer, it will make you better.
If you're an actor, an athlete, a musician, or just an ordinary person, Feldenkrais helps you become more aware and thus, more able to enact your intentions within your body.
It does not, in itself, teach IP/IS, but it makes me more able to feel and understand the things said on these boards.