Shattenkirk was much less D-zone gaffe prone, once he was paired up with Schmidt toward end of Pens series. Shatty-Orpik just never worked. I don't think Shatty felt confident moving the puck to Orpik, and so he got trapped more and made more panicky passes to other guys on the ice.
Honestly though, these pairings really aren't terrible, especially for the regular season. But it means we have to find a way to protect Schmidt:
Nisky-Orlov
Carlson-Schmidt
Orpik-Chorney
And then give the best of the young Hershey guys the 7D slot
In the playoffs, you largely hide that 3rd pairing, like most teams do anyway.
The problem is, when do you hide it? It's an offensively inept pair that shouldn't be given way more O-zone starts because it will effect the team offense. And it might not be able to hold its ground defensively due to a lack of speed (Orpik) and defensive awareness (Chorney)