It was a 4 game gimmick series where Marner found himself as the least played forward by game 3.
If Cooper was so impressed with Marner in game 1,2... he wouldnt have made him the forward with the least mins in game 3. Im fact the coaches admitted the changes in game 3 to the lineup were because they thought the team was too perimeter. So.... yea a major change was to drop Marner to the least played forward. By next year, some of the Canada forwards who played more than him in game 3 will be paid 1/2 what Marner wants! So it would seem Cooper seen exactly ehat we have seen over the past 9 years.
Sure Marner made a play 3v3 in OT in game 1, and couple plays in game 4... but him riding the pine by game 3 is more telling than his couple points in game 4. Also.. that lineup was the leagues best players... he doesnt have Mcdavid, Crosby, Mackinnon, Stone, Point, Marchand, to hide in the shadow of, or carry the play, or carry the leadership load.... anywhere he goes, for the money he wants, he is supposed to be THE GUY for all the above.