I tried reading the article explaining how they calculate that stat and my head nearly exploded. However, looking at the stats they have it does not look like Iggy is the biggest boon to a team's succes, but that his absence from the line-up makes the biggest difference of all of the players sampled. Other players seem to have a much higher positive rating, while Iggy's positive rating when he is on the court is not that high, but the team's rating when he is not on the court is much lower and very negative. Taken on its face it looks like he is good at making a really bad team look a little better than average. Would his presence make as much of a difference on a better team?