I like the idea but it needs to be more in depth. Right now, I don't care for it or take much notice of it. I would like to know how many mistakes a guy has made over the course of a season without tracking it myself.
Without knowing how a +/- impacts a play, I completely ignore that feature right now. Also, it would be interesting to understand if there is a correlation between that performance metric and player ratings. One would assume there would be a link to play diagnosis, but FOF doesn't always follow football logic.
In BELCO leagues the +/- is ripped from gamelogs and counted on a seasonal level. If you browse around at some of the stats you'll see that +/- means nearly nothing as far as I can tell. Sometimes guys have great seasons, but a - score. Other times guys have mediocre seasons but an overall +. It completely seems random.
Which tells me we probably haven't cracked it yet.
Or it's total junk and worthless as a counting stat.
My feeling was it was simply showing us the dice roll result. Nothing more, nothing less. From there it's up to us to determine if it's just a bad die roll or if it was a result of a bad play call, a player out of position, etc.