when riding in deep snow you want as littel footprint as you can get. too wide and it rides on the snow and can't get to trh ground for any traction. you want the tire to sink through the snow to get to teh ground.
True and Untrue.
Lowering your tire pressure can help you a lot in snow, mud, or the sand. When you lower your tire presure more of the tire hits the surface which means the sides of your tires will be hitting the road when they normally wouldn't. So therefor you would have more traction.(Also i don't know how true this is on winter tires for a car, but when you drive on the beach, go Mudding, or get stuck the first thing you do is lower your tire pressure, but that is on all terrians or Mud tires like the ones on my Jeep)