I used http://www.calorieking.com/calories-in-hot+dog.html to assemble some nutritional information for some of the hot dogs I ate in my hot dog experiment. Beginning with the USDA guidelines for the percentages of our diet that should come from fat, protein, and carbs and then assuming that a person consumes 2000 Calories per day, I arrived at the number of Calories that should be consumed from fat, protein, and carbs. Then I used the 4-4-9 information regarding the Calorie density of carbs-protein-fat to calculate the grams of each that should be consumed per day by an average adult. Then I looked up the grams of carbs, protein, and fat in various hot dogs and calculated how much of the recommended daily allowance (RDA) each hot dog provided in each category of macronutrient (fat, protein, carbs).
After all that, I got to thinking, "hot dogs are salty." Many people have trouble with high levels of salt. I wondered how much salt was in each hot dog. It turns out the Costco hot dog is the saltiest by almost double the other hot dogs. Although young people can process 2.3 g of sodium a day, older Americans (beyond age 50) are not recommended to exceed 1.5 grams of sodium. Therefore the Costco hot dog should be off limits for older people. The Costco hot dog is OK if you are only eating 2 meals a day, but although inexpensive, it is not a great source of energy compared with other choices like vegetables, fruits, and nuts.
So my misconception was that I thought 4-4-9 was the balance of carbs-protein-fat that people should consume. I didn't know if that was in terms of grams or Calories. What I learned is that 4-4-9 is the ratio in Calories if one is to consume energy equally in grams from all three energy sources, which is not what is recommended. What might be possibly more useful is knowning that the USDA recommends a 6-3-11 ratio of fat-protein-carbs in terms of Calories. I used to count calories using the Weight Watchers points system. It simplifies the point value of each food and allows a participant a specific number of points per day. You also get a credit in the formula for increased dietary fiber in your foods.