Bill Clark can't help but smile when he talks about defense. He's been a college head coach for six years and four seasons now, but that side of the ball is his specialty. The UAB head coach tries "to be balanced" in the time he spends with his offensive and defensive units, but "I always seem to matriculate over there (to the defense) a little bit more as the season goes," Clark said after UAB's second scrimmage of preseason camp. "As the season goes, it's a time when you've