I didn't read TFA but I wonder if this study consider the quality of those calories, e.g. in America we try and diet by eating one cheeseburger instead of two, of course we could have eaten 5 apples instead, been full and satisfied, and gotten some nutrition as well.
Who would want to eat five apples in one sitting? Even if I were hungry, I'd probably just stop at one and wait till the next meal. At least pick a more appealing fruit like an orange.
But seriously, I dropped from 205 pounds to 170 and have kept it off for years with virtually exercise and with the only change to what I'm consuming being that I never buy any beverages with calories. Mostly stick to water with some diet pop on occasion. Other than that, I just cut back portions and eliminated snacking between meals.
Funny thing is, I motivate myself to diet with food. I have a very strict rule that I never eat out/order in unless I'm below 170 pounds. Then I'll get whatever food I want and have one meal where I eat without restraint. After that, I have to diet off whatever I gained and repeat the process. Keeps me happy, and sure beats going vegetarian and/or spending hours a week in the gym.