People who say "just eat less" aren't thinking like engineers. Engineers don't get to ignore the wrenches thrown into the works by reality. If seemingly simple advice fails for almost everyone, then the advice is flawed and someone thinking like an engineer has to figure out how to work around those flaws. I don't know if low-carb diets are the full solution, but I think they're at least part of the solution. Avoidin…
The advice is sound. You get fat from the stuff that goes in your piehole. Stop putting so much stuff in there. The flaw is not in the argument. The flaw is in the people. THAT's thinking like an Engineer.
Reminds me of a story (no idea about historical accuracy): When the chief propagandist of the UDSSR was invited to a scientific conference he talked about all the positive effects of socialism, how it will solve all problems and so on. When his talk was finished the scientists unsurprisingly questioned him about his talk, because of all the prominent problems with socialism. His answer was simple:
"The system is perfect. The people are the problem."
If your system is 'perfect', but the people are the problem, maybe your system is shit. No one would use an engine that could go near the speed of light but killed all passengers in the process.