I subscribe to the Lyle McDonald newsletter. I thought this week's was extremely interesting. Here is an excerpt (he's interviewing a contestant from 'The Biggest Loser'):

BL: Our goal was to lose 1lb per day (3500 calories). Our particular trainers philosophy was that she was going to BURN it off you in the gym and if you had a poor day in the gym the VERY first question that was asked was "Did you eat". It had to be pounded into us that we had to eat. It seemed counterintuitive for many of us in a weight loss contest but it proved itself out when a teammate of mine upped his workouts to 6 hours per day and shrank his food to 500 calories per day (on his own) and only lost 3 pounds in 7 days while everyone else averaged 7-10.

My comments: This is an interesting idea as it's something I noted years ago and have commented on previously. The combination of lots of exercise with big caloric deficits tends to work extremely poorly and seem to slow instead of hasten fat loss for some reason. This is part of why I strongly recommended against lots of exercise in the Rapid Fat Loss handbook; the deficit inherent to the diet is already large enough to the point that adding a bunch of training seems to cause more harm than good. I don't know if the issue is simply metabolic slowdown or if there's something else going on (this my current new project now that the protein book is finally done) but I've seen it happen time and time again: excessive caloric deficits plus excessive amounts of exercise seem to do more harm than good. If you are burning a lot of calories through exercise, you have to eat. If you want to cut calories hard, you have to reduce activity.

After spending a good four years on weight loss boards and maintaining a +/- 25 lbs loss myself it appears that weight loss (& maintenance) is not a matter of eating as little as possible but instead-- of finding a *sweet spot* where calories are high enough to maintain metabolism but still the deficit is low enough--from diet or activity to allow for weight loss.