do the coaches who take the time to mine data compute the +/- themselves, and find it as useful as bistiza suggests?
in general, id be all for making it easier for new coaches to get up to speed on what makes players good. i think the abstract, what is a good player, should be fairly clear, but the complexity should really come in when you are trying to decide what players to put together to build a team. i think its kind of silly how little info the new coaches are given on this stuff.