was that he needed the basketball portion to be more believable than what you usually see in sports dramas. In this instance, I'd say I agree with him. Too often in sports movies, it's just so hard to buy the story because the actors can't pull off the game.
You can get actors to play well enough for some weekend pickup games, or even something like White Men Can't Jump. But Spike was really concerned that this story about a top recruit have a player who you'd believe was a top recruit.
Generally speaking, we all can recognize top sports athletes better than we can spot top acting talent, so for something like this it's better to try to get an athlete to deliver his lines right than to get an actor to be convincing as top hoop star.
This is theory anyway, and Spike's argument as he presented around the time of the movie.
You have to judge for yourself whether or not he made the right choice.
But Hill Harper ain't but about 5'5", so it wasn't gonna be him.