Bob Knight was once feted for being a guy who could win with a largely Caucasian team. But, when asked about it, he simply said "anybody can play basketball -- black, white, blue, green."
Bo Ryan's style tends to favor good 3-point shooters and big, strong post players -- the type of guys you might find in Wisconsin, and at the risk of sterotyping, guys who play positions that are (stereotypically) seen as ones white guys play. Northwestern uses the Princeton offense, which relies more on ballhandling and shooting ability (and to a degree, craftiness), and always seems to have about 3 Europeans on the floor.
But, in large part, I sense this to be a big of a misnomer. Indiana was always seen under Bob Knight as a primarily white team, because he always seemed to have a Steve Eyl/Todd Meier/Todd Jadlow out there to set picks or a guy like Steve Alford or Pat Graham to shoot 3-pointers. The majority of Tom Crean's recruiting classes have featured African-American players, and next year's will, too. Of the 8 guys I know of who have verbaled or signed for the next 3 years, all but one are African-American. Wisconsin always seems to have a big white post player with a last name I'd associate with being from Wisconsin, but their leading scorers are almost always black players.
