I expect people who have had gastric band op also go through phases where their weight loss stalls as well. I dont really buy into the starvation mode theory very much, undoubtably it will have a knock on effect on metabolism, but if you eat very little you will lose weight. It may not be the same regular amount each day or week, ive been dieting long enough to understand the foibles of weight loss to know that its hard to predict how much you will lose, or how regularly.
I do however really buy into the set point theory, as it seems to fit. Your body has a natural weight set point, when you go below that your body will try to recover the weight lost and may stall for a while. Keep going and the body readjusts itself, and you start losing weight again. It happens to me on a regular basis, and is part of the ups and downs of weight loss.