from Tim Wharnsby of CBC,

If the league looks at employment of a coach's challenge, there would be so many dynamics to consider.

How many challenges would a coach have in a game? Would a challenge be limited to certain types of plays? Would a failed challenge result in a penalty? Would a challenge be allowed in the closing minutes of a game? If so, coaches may use a challenge as a delay tactic to rest up his star players.

There is no harm with a trial and error period in the preseason in order to tinker with all these components. There is no harm in trying to get it right. But I'm not sure the NHL is ready for such an undertaking as a coach's challenge.

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