Yes, he was an outlier in that way. But I was speaking of your original post. What Adrian Peterson did in one year to recover from his surgery was an outlier, which I attribute to freakish genetics. Frank Gore is threatening the all time rushing title through doggedness, which again, his longevity in maybe the roughest position in the NFL, is freakish. They are outliers in the long run because it just doesn't happen that way for most RB's. IE, "You can't make the club, if you're in the tub."
As for Gurley, it hasn't worked out for the Rams for whatever reason, because he did not last. We just gave up a helluva lot of money dumping him. If he had worked out for us, we wouldn't have heard from Sean McVay most of last season things like "Todd is ok....cleared to play.," but then he was sparingly used when we needed for him to take over a game(s). One game was all we needed to be in the playoffs, and a normally healthy Gurley would have affected the whole season.