Emotion can be both a great boost to a team's play and a great detriment. A good example to me from this past year was the win over the Eagles followed by the loss against the Seahawks. The team was so up for that Eagles game that they were very drained the following week vs. Seattle.
It's really about finding that right balance. What that is, I have no idea. Mora is in the same sort of camp as Gruden and Cowher, two very visibly intense and emotional coaches that have won Super Bowls recently. Then you have someone like Belichick, who is definitely hard-nosed, but doesn't have the same sort of "sideline tenacity." One could argue a coach like Dungy because of his lack of intensity is why his teams have not yet gotten over the hump and gone beyond conference championship games.
It just comes down to how you best relay that to the players.
"Vincere scis, Hannibal, victoria uti nescis" -- Maharbal, 216 B.C.E.