I'd love to see a breakdown of those numbers as a 3rd pairing guy vs a 2nd pairing guy.Struble was the worst defensan in terms of on-ice scoring chance differential (low 40%) even with relatively easy deployment.
People are always blinded by the shiny new toy!
We know he struggled when he got bumped and the work load overwhelmed him a bit.
I don't think I've ever relied on analytics alone when there are so many other factors involved.