I would agree with that. And I will look into the other stuff.
I've experimented with various home style diets, carbs and no carbs, while running grueling mountain courses. Carbs kick in, for me, and the fatigue wall falls. I know, one guy experiments don't get published. LOL.
It's a question of paying attention to how much activity you are going to participate in and planning accordingly.
On the whole, though, far too many people eat like cows. Fill the trough and they eat till it's gone.