You probably shouldn’t eat a whole 500g box of Raisin Bran on the couch while watching television, but that’s pretty much what I do when I buy a box of cereal. To me, the box is just a 2000 calorie pack. I start off eating about 3 or 4 bowls with almond milk. Then I just reach into the box, and eat the rest like popcorn. No, it’s not ideal. But I do it all the time, and I don’t worry about it much.
Sometimes I’m genuinely hungry, other times I just finish off the box because I can’t stop. I should probably stop buying cereal, or cook something more substantial (i.e., with water and fibre) if I’m really hungry. But, I’ve been eating massive amounts of carbs at night, before going to sleep, and I’ve still lost 28 kg.
Since excess carbs aren’t easily turned into fat (de novo lipogenesis in humans is minor), this occasional overeating isn’t an issue when you eat low-fat (< 10% of calories). Still, it's always best to aim for approximate energy balance, and not to continually overeat. But on the Starch Solution, eating a whole box of cereal isn't "blowing the diet". It barely registers in the scheme of things.
(Yes, I'm watching ArchieLuxury.)