Yea, because NO ONE else has black as their primary color. Nothing says "SIOUX" like a sea of green inside Mariucci Arena. Black? That just blends in with everything.
I, for one, don't like the Sioux "third jersey." If you're going to do a third jersey, at least make a template or logo change on the front. A black jersey would be cool if it had "SIOUX" written diagonally on the front and maybe small Sioux patch logos on the shoulders.
As long as Nike continues to invade college hockey, you'll see the templates that are easily changeable for doing other team jerseys. Before long, Sioux hockey will look like Oregon football.
Just my two cents...