Most coaches do similar things like that, like TBL going on that run with Marc-Andre Bergeron
Or Car with DeAngelo last year, Dallas with Klingberg, plenty of contemporary examples of sheltering excellent offensive dmen
They don't roll those guys out on the wrong side and PK in big minutes
This is one of those things where a player's 'true' ability is hampered by chemistry and you see in D pairs more than elsewhere on the ice usually.
I always bring up Muzzin Martinez as an example, at the time Muzzin was surely a #2 and Martinez a #4-5 but they were literally league worst in goal differential because they were absolutely toxic for one another.
Roy and Durzi are opposite ends of a battery in similar ways, it's just one way in which TM gets the absolute least out of his players while him and Blake leave better options off the roster altogether.