Jen, check to see if your cavities, between panes, are filled with argon?
A sign that your windows are working well, and internal heat is not being reflected out causing outside fogging, under certain conditions.
Once again a misconception regarding global warming, I wonder how many scientists make similar mistakes? You need all the facts to make a decision, very difficult when the parameters are in constant flux, often for unknown reasons. Lets put it down to global warming, or the devil perhaps.
By the way you didn't say if you "looked up" the grave robbing story, on the green piece thread.
What Is It Good For - Alphabetical