I never said that eating less was easy. I am not sure how you read that from what I wrote.That's just it. It is easy. It's absolutely, effortlessly, ridiculously freaking easy. If you're lucky enough to have my metabolism. I can buy basic, average quality food, eat to satiety, binge during the holidays, occasionally eat an entire bag of candy, and barely move the needle on the scale. It's not fair! But it's reality, and my luck with regard to metabolism is compensated for by other things about myself that are less fortunate.
While the arguments from conservation of matter and energy are obviously true, they are not the best guide to find actual success in eating. Human bodies are fantastically complex systems of systems. Human metabolism is a chemical system with an insane number of components. Conscious decision is only a very small part of that system, with the vast majority being controlled by autonomous chemical and neurological processes.
Attacking obesity by focusing on portion control and willpower seems rather like trying to control a PC by carefully fluctuating the voltage coming into its power supply.
So when news outlets start reporting on some part of the problem other than portion control, don't take it personally; take it as looking at the big picture.