Like I said, there isn't a metric available that supports what you're suggesting. And it isn't only last year when he was hurt. He's been a fringe NHL player for at least 3-4 years now. Probably longer if it wasn't for Torts coaching his niche.
20 years ago Girardi would have been a very solid defenseman. In today's NHL, not so much.
Yeah I understand your concerns, and would be lying if I said I was not concerned. But like to see how things play out and hope for the best.