Harris would be chasing sidelines if Mariota goes wide and they lose the edge.
When it comes to instincts and knowing where to go, Harris > Roberts.
Just plop Harris on the left side as that is where Henry has almost 1/2 his yards...
As much as I think Harris moves slow, this could be a game for him so I'm not sure he'll be inactive as you have KVN (assuming he can move 100% ) and M Flowers both have the ability to get to the sideline and contain Mariota. Throw Chung in there too but he and DMC might be sticking to Walker all night.
I also wonder how Decker and Matthews will do as they both have a decent amount of experience going up vs the NE D.