I would have to agree. This much body fat loss would be unlikely to lead to no weight loss. Unless it was over a long period of time with a significant increase in muscle mass (or manbe water retention somehow). I would recommend getting a more accurate estimate of body fat to verify the numbers. Body fat estimation is not exact and there are so many variables. (Hydration, where and how you gain/lose fat, etc.) And muscle is much denser than fat, so inches would certainly change.