When I practiced from the sand during the 2007-'08 off-season, I hit shots from 10 yards out exclusively. After the 2007 season, my short-game instructor, Dave Pelz, did some research and discovered that the average distance of a sand shot on tour was 10 yards. So that's what I practiced (left). Thirty feet, nothing else, though I did create different lies for variation.
When the 2008 season began, I found that if a shot was a bit shorter or longer than the 30-foot norm, I needed to make only a small adjustment to compensate. The practice strategy really paid off. At one point, I hit 28 consecutive sand shots within three feet of the hole.