I have my doubts about the whole "cold weather" advantage theory.
I'll concede an advantage in some non-physical ways like how to throw a cold ball but to suggest that sub zero temperatures will affect Packers players less than it will affect Saints players is nonsense to me.
Cold is cold no matter WHO you are and its miserable. I'd like to see a poll of the Packers players as to where THEY would rather play. 0 degrees and 20 mph winds or the Mercedes Benz bowl.
Plus, you make it sound like every Packers player grew up in the arctic north. There are plenty of players that hail from Florida, Texas and California. Do they give them a special "Cold Vaccination) when they sign on?
The only advantage is Home Field advantage and even that will take a hit as many fans elect to stay home and watch it on TV.