Small sample size is also possible but, quite honestly, the best RF is going to make less than 2 plays per game. The top 10 in most leagues I've checked have a range factor between 1.6 and 1.7. If you can stick a 6 range DH out there and have him make 1.25 with 20ish errors/negative plays, you're not losing much. Less than half a play per game difference between a DH and a GG candidate isn't much. Obviously, you'd rather have a GG candidate and a Silver Slugger out there but, if you can't have both, it's a really good place to skimp on D.
Assuming, of course, that what's happening with Nieve is what would happen over several seasons.