I'm a bit confused as to what Helen is suggesting as well.
Any calculators on maintaining weight loss and weight LOSS in general are only estimates. There is no one or nothing that can tell us for SURE just how many calories we need in order to lose a certain amount of lbs per week. As is there is nothing to tell us for sure the amount of calories needed to maintain weight loss. It's all basically trial and error.
I'd have to agree with the terminology of why "diet". I mean you do plan on keeping the weight off forever. Therefore you want to find something that you can do forever - a lifestyle change - NOT some diet. Watching your calories for the long run IS a lifestyle change. Incorporating better eating habits IS a lifestyle change. NOT a diet, per se'.
But weight loss can only occur when you create a calorie DEFECIT. By either eating less then "normal" or moving more (LOTS more) or prefably - a COMBINATION of both.
I agree with Jay. I could exercise 24/7. There's only so much calories exercise could burn off. Unless of course you're running marathons everyday. If I don't monitor/restrict my calorie intake - then I just don't lose weight. Period.