Israeli artist Emanuel Gat’s brilliance as a dancer is obvious upon a moment’s witness of his animal grace and controlled concentration. His importance as a choreographer has been elusive to me, however, until the world premiere of his pearly Winter Variations in Reynolds Theater, commissioned as the second program of the 2009 American Dance Festival. Gat’s work has previously seemed broken — or if not broken exactly, then concerned with brokenness, interruption, separation. For a viewer interested in wholeness and harmony, his oppositional, argumentative compositions can seem arid and gratuitously antagonistic, despite their extraordinary qualities of movement.

Winter Variations, an hour-long duet for Gat and his performing partner Roy Assaf, somewhat clarifies Gat’s underlying concern with the deep duality of life — it lets us know that there is a philosopher beneath that irritating bad boy who so abused Mozart’s Requiem in his dance K626 that premiered here three years ago — and that clarity allows greater charity with his sometimes infuriating methods. Winter Variations grew out of a shorter work, Winter Voyage (danced at ADF 2005), and its conceptual completeness raises it above its own at times monotonous shortcomings. The ideas latent in Voyage are well formed in Variations: to my astonishment, one of them is not separation, but the elastic inseparability of certain things.

Like a form and its shadow, or sound and silence. In his masterful stage design, composed entirely of light and a pair of audio speakers hanging side-by-side just above the danceable space, Gat and Assaf, in simple gray clothes, dance precisely through a world of shifting grays, on and within fading and darkening grids of light. With a litany of crossing and opening motions, covering and revealing and aligning themselves and each other, they work from stuttering pauses into whipping waves of muscular poetry with brutal grace. In contrast to earlier pieces in which the dancers work against a particular music, in Winter Variations the pair works in telepathic tandem with each other and with a medley of disparate songs united by their mournful resonance: Jessye Norman singing Richard Strauss’ “Im Abendrot,” Dietrich Fischer-Dieskau performing the Schubert Lied“Die Krahe,” Riad Al Sunbati, accompanying himself on the oud, and a re-mix of the Beatles’ “A Day in the Life.”

“I read the news today, oh boy….” That is indeed enough to bring a man to his knees, to drop him out of whatever tender connection, heroic rescue, or joyful swing he may be stretching and snapping, to shrink him and dwarf him and send him knee-walking rigidly down a fine line before the maze returns him to himself, his partner, his form or shadow. But Gat’s overuse of this powerful imagery renders it dull. Near the end, the dancers press on their skulls, cover their faces, hood their heads with their arms, as if they too are getting sick of all this. In the final scene, the two struggle prone across the floor in feats of spasmodic wriggling and rocking, like seals dragging themselves onto a beach. It is a relief when they get there.

Winter Variations repeats June 24. See our calendar for details.