Speaking metaphorically, we might liken it to dance or song, intending in doing so, perhaps, to suggest that the poet like the dancer or the singer must exercise an absolute control over even the most subtle nuances of sound and movement.
And yet must do so with such apparent ease and self assurance that nothing seems at all contrived or difficult, just a few words thrown like boards across a hole. Not that it really matters anymore. That curling ash. That wisp of smoke. This wind driven snow at your ears.
A disembodied voice that cries throughout the vast and terrifying distances of night for release from its suffering. Or what is within and yet beyond that merely human voice but clings to it like fire: truth beyond form yet seeking form in order to exist. Sheer illusion. Madness. Sleight of hand.