Between the title of the article and the photo, it's clear what this article is about. While the knee-jerk reaction may be a resounding "not at all," it's worth a bit of thought...Passing laws would be the only way to keep people from building huge houses, and think of the problems: what do we do with the huge houses we already have? How would one advocate a law that literally scales down the American dream?
But houses, big or small, do have an impact on the environment, and getting more of them LEED certified means that there will be less impact. (Note that we said less impact -- less of a bad thing is still bad.)
The alternative we'd like to see pursued? A zero-net energy requirement for homes over a certain size. This is obtainable now, with current technology: ground-source heat pumps; lots of photovoltaic panels; solar hot water. It just takes money.
And if you've got the money to buy a huge, huge house, we don't see any harm in making it a little -- or a lot -- more expensive. Given the size of the 'green' homes profiled in the article, getting the energy usage down to zero would make the biggest long-term impact.
image Douglas Healey for The New York Times