That's not entirely Hartley's system at fault, it's the fact that Smid and Engelland have no mobility, while Russell and Wideman don't muscle anyone off the puck. And Diaz... I don't think he could muscle someone off the puck if you sent him to Kingston to play with Sam Bennett.
Wait until we see Hartley's system being run by guys like Hickey/Rafikov/Wotherspoon who have both strength and mobility. It'll be just like the Gio/Brodie pairing. Not that we're in any rush at all to get rid of Russell/Wideman; I'm just sayin'.