Aha. Now we're getting somewhere. Thank you!
According to Fangraphs, "Replacement level is simply the level of production you could get from a player that would cost you nothing but the league minimum salary to acquire. Minor league free agents, quad-A players, you get the idea."
Fangraphs now has JBJ's dWAR @ -0.4, IOW he's not as valuable as one of those guys described above. You can call up a AAAA outfielder and actually GAIN defensively. What could possibly be inaccurate about that, right?
The bigger picture is that this not only applies to JBJ but to every outfielder in baseball. I think we can all agree that there's a flaw there but since we don't know where that flaw is fangraph's dWAR calculation could very well be bogus regarding every outfielder in baseball. I mean, it's highly unlikely that whatever is "wrong" with JBJ's calculation only pertains to him, right?
In addition, there are at least 5 (that I know of) sources who calculate WAR and they can't even agree on it! Think of it this way. If you were looking for a car to give you the best gas mileage and every manufacturer calculated MPG differently which car would you buy based on mileage?
I'm not saying WAR is useless. It's very good at telling us what we already know. When we see a player with a WAR of 5.0 and another player of 0.0 it's pretty safe to assume that the 5.0 guy is a better player than the 0.0 guy. When we see a player with a WAR of 1.0 and another player with a WAR of 1.2 we can see that those two players are about equal - but we already knew that! But when they try to convince me that JBJ is worse defensively than a freakin' replacement player I'm going to challenge it... every time!
I may be old and my eyes failing a bit but my ability to recognize the obvious is still intact.