I'm not so sure. Remember, the veterans on this team remember running the table whilst wearing the away jersey, even CHOOSING to wear them in Detroit (that year, AFC had the choice of jersey). Unless it's 100 degrees and sunny, I don't think either jersey choice provides the Cardinals a boost.
True, but they got the psychological advantage by wearing white that year since we'd been on the road for every playoff game, and we were underdogs going into the SB IIRC. Even if we were favorites, they were trying to keep that mentality of fighting on the road (despite the SB being 85% Steeler fans).
This year, they've been home every game, and the favorite, and the favorite in the SB. Cards have the "us against the world" mentality. I think the Steelers would get the advantage wearing black. We're at home, we're the favorites, we've been here before, we are going to crush you. Wearing white takes a little of that edge away.