Why do some people pack on the pounds effortlessly? It’s not always genetics and it’s not always gluttony, and you can’t always blame it on lack of exercise. Indeed, becoming overweight is often a result of some simple—and easily correctible—bad habits, especially when it comes to dining out.As we began researching Eat This, Not That! Restaurant Survival Guide, we discovered plenty of egregious examples of super-fattening foods in both America’s supermarkets and our chain restaurants. And we learned that if you simply know what to order and what to avoid, you can shave off pounds effortlessly. For example, does On the Border really need to stuff more than a day’s worth of calories into its Dos XX Fish Tacos? (Remember when fish was healthy?) And shouldn’t Chili’s warn parents when a selection...