It's a line that always got laughs, but it also makes perfect sense. Behind the brothers' daredevil athleticism and their stunning acrobatics born of great flexibility, strength and fearlessness lay a foundation of unerring technical control. Once you've seen their explosive stair dance in the film "Stormy Weather," you never forget it, and their work is so memorable because of the intertwining of ecstatic abandon and musical precision. Fayard Nicholas and his younger brother, [Harold Nicholas], who died Monday at 79, wove time and energy together into an electrifying double helix.

In the 1992 documentary "The Nicholas Brothers: We Sing and We Dance," ballet star Mikhail Baryshnikov calls the pair "the most amazing dancers I've ever seen in my life--ever." In footage from a home movie shot by their mother, the brothers are seen fooling around with [Fred Astaire] on a Hollywood back lot, the three tappers aligned and synchronized, Harold and Fayard gliding a shade more smoothly than the famous Fred. And one wonders, what if the Nicholases had been given the star-making movie vehicles that Astaire enjoyed?

Whom did the Nicholas Brothers look to? Somehow they simply gazed inside and drew upon their own musical instincts. Born as the Jazz Age was dawning, the brothers had a rich education in their own home. Their parents were pit musicians for various black vaudeville houses. They taught their sons about rhythm, but the boys taught themselves to dance. Harold was six years younger than Fayard, compact and naturally acrobatic, with high cheekbones and catlike eyes; Fayard was taller, leaner, more the musician.