doesn't want it. I recall being near the bench at a game when two guys were coming off on their own and I heard "what the f do you f'g think you're doing?" It's really up to the staff, especially when the bench is shortened or there's a matching contest going on. Scotty Bowman would occasionally mix up lines/pairings so that the guys on the other side couldn't make decisions on their own. And some coaches are control freaks about changes.