Funny - the idea of all things being connected is something i've been studying quite intensely lately and - BAM! - here it is, popping up on my favorite forum community! Synchronicity at its best, i think.
I've felt that emotional connection once in a while, where i and another person are completely on the same wavelength. It's something that i have found makes the difference between a "good" relationship with someone and an outstanding, mind-blowing experience. I don't think sharing this complete one-track-ness with someone during a scene puts anyone in danger; it's being super-coordinated with another person. It's "being" before thinking about being, and that is essentially the connection i think those in Dom-sub relationships strive to have.