That is true for me. It can be disappointing when I'm not connecting, because this relationship depends on trust-in my improvising partners as well as myself. When I improvise with people I have never played with before, in a public performance, I feel as if I'm taking a big risk. It is a test of your abilities to understand the temperament or style of another person in an instant. I have to be an artist and critic without thinking.
Improvisation is about acting without time for thinking.
I'm receiving and transmitting instantaneously. My action is physical while my listening and interpreting happens on a pre-cognitive level. I could say more, but maybe I am becoming pedantic now. My relationship to a fellow player makes the difference. My instrument can do things that traditional instruments don't and vice versa.