Their job is to coach NHL players and game plan against other NHL players. They are at ice level and actually watch the games live, evaluating players is most definitely something they do and are likely good at. What are you trying to prove here?
Okay now we can get somewhere. Yes, as I said in my initial post that agreed with you, coaches OBVIOUSLY know about most players and their abilities. They are at ice level every game and they watch film for specific plays/situations/formations, etc..
But the days of head coaches sitting down and watching film after film of opposing teams and dissecting those films into personal assesments of players are over. That is handles by video crews now and partially the coaching staff excluding the head coach.
So my point was that I half agree with you that coaches know about other team’s players. But coaches dont know everything about them and sometimes it takes multiple games against them until they have a true understanding. Also, some coaches simply dont care about most others team’s players in the sense that their staff is meant for that. Head coaches have a ton of responsibilities and film was taken off their hands around the 00’s.
Just as an example, Hynes of NJ has previously said before ‘well I know (insert young stud here) is a great player and he does some things well, so I and the staff will do our best to match up against him so he cant score’. Obviously thats not a quote but my point in using it is head coaches dont know everything about other team’s players, they know the main aspects of each line and big name players. Thats why rookies, sophomores, or late bloomers always shine early on moreso than they used to.
Basically I agree with you but to an extent - head coaches back in the day like Herb Brooks would be on film for days. Not anymore.