That's right. He's looking at him saying he's a 5-6 WAR player, which is an all-star or better; you and I, who are skeptical of the relative value of defense in the WAR equation (you call Heyward above average; I'll go further and say he's the best defensive RF in baseball) and do not value him the way we would value a player whose 5-6 WAR were mainly made up of the offense component, maybe Joey Votto or Paul Goldschmidt.
WAR has become a handy shorthand for valuing a player and is never accompanied with all the disclaimers its authors give, talking about major year-to-year swings in dWAR and using it as an estimate not an absolute and so forth. And if it is going to take on that kind of prominence, it simply must be improved.
Hey, I understand the surface logic that a run saved equals a run produced. But consider this: nearly every run is produced. Not every run is saved. You don't have that many chances to do something extraordinary on the field to save runs. Does that make sense?
There's something wrong with the weighting of the accrual of DRS that gets guys way above the standard deviation accrual too quickly. The impact of X DRS needs to be tamped down a bit, maybe by half or so. And it bothers me a lot that certain skills aren't picked up in dWAR, like a 1B's ability to pick it (they aren't all the same) and a lot of things about catching.
I think in a few years somebody is going to refine defensive statistics to incorporate those things and recognize the relative weights of defense and you advanced stat guys will say, "of course. It's always been so," after so many years of defending this WAR shorthand.