I used to find it irritating on the 734 when the F/O set up his own display and CDU and then told me what he wanted displayed on mine. When I first when on the fleet the principle was that PF chooses what he wants then PNF monitors him by displaying what he feels comfortable with. We then got some new training Captains who started teaching the new F/O's this habit of trying to tell the Captain what he should be displaying but to my mind it stops him from properly monitoring. If he wants map fine, if he wants another display then that should also be his choice, likewise the CDU page.