Agreed, carb loading is a possible strategy that may be used as a method to store more glycogen in the muscle prior to a long endurance event. However, it has a specific protocol starting a week out leading into the night before. This is individually based and can go easily wrong. There is also some controversy if it’s even a valid strategy, especially for a road cycling event where getting nutrition is not as difficult, as opposed to swimming, running or even MTB.
That advise that you gave will do nothing more than pack on extra pounds at best, and at worst cause digestive distress, wild blood sugar changes and/or poor sleep.