Doesn't each team only get one challenge per game though and it would use their timeout?
I think MS's point is they might stall for time while their own staff decides whether or not a challenge will be successful, either through discussing what they saw or using their own video capabilities (especially in the age of smartphones and such). That way they kind of get to have their cake and eat it too -- it'd be an abuse of process along the lines of "getting confused" following an icing call and making an illegal change before being told to put your now-less-tired players back on. (This should be penalized even if accidental, in my mind).
I would rather just extend the powers of the video review on goals/no goals. Too often a goal gets reviewed and we hear "that's not reviewable", if it obviously wrong then allow the review guys to fix it - there should be no need for a challenge in such circumstances.
Part of the problem is how often the "Toronto War Room" actually gets it wrong, though. It's embarrassing, frankly, when TV stations and people at home can often see easily what happened, but in Toronto they either "don't have the angle", or don't understand what kicking a puck means under their own rules, etc.