I found this report quite fascinating; he seemed to me more a hedged trader than a straight dice roller:
January 16, 2011 6:00 PM
Las Vegas sports betting legend Bill Walters has never had a losing year – a winning a streak that’s made odds makers call him the “most dangerous sports bettor in Nevada.” Lara Logan reports.
Sports Bettor Billy Walter’s Winning Streak
Las Vegas Professional Gambler Tells “60 Minutes” He’s Never Had a Losing Year
Jan. 16, 2011 http://www.cbsnews.com/stories/2011/01/13/60minutes/main7243443.shtml