Well, it is kind of a catch 22 with ventilation. First off, where does the moisture come from? it is a byproduct of the bees consuming honey. When you provide upper ventilation, you are also allowing heat to escape (just like leaving a window open upstairs in your home). When heat escapes, it requires the bees to eat more honey to keep warm. So the best way to reduce moisture is to reduce honey consumption. My preferred method is to increase the insulation value of the hive and have the highest insulation value above them. this way any condensation that does occur will happen on the walls and not above the bees. Also, warm air holds more moisture than cold air, so by letting them keep the heat in the hive, more water stays in the air so there is less condensation. The best way for a langstroth hive is to use a quilt box like the Warre hive. It allows moisture to be wicked away without loosing any precious heat. If you are not familiar with Warre's principles, a free version of his book can be downloaded here -> bit.ly/warre well worth the read for many reasons.
Yes bees can survive with upper ventilation, but it requires them to consume more honey and it a drier environment. Just like you prefer more humidity in the winter to breath, so do they.