Rhythmic Synchronization

How is it that we can be in a total flow state and still be exhibiting good time or good rhythm? It's almost like you're in a trance or youre you're mesmerized at that point. There much, much different than a groove that doesn't budge. And what about an orchestra with no metronom, or no click but following you conductor,. With the celerandos and ralentandos and frematos and tempo and meter changes? There's hive trust and cohesiveness in full display. Along with that type of rhythmic sensibility on full display. The only real perceivable variable is the live musician.