Rory DeLuca's weight loss journey illustrates that eating more and doing less cardio can lead to significant results; he lost 30 pounds and 9 inches in three months by incorporating strength training and interval cardio instead of traditional methods. His regimen included whole-body exercises, sustaining high heart rates, and consuming nutritious meals with balanced proteins, carbs, and fats. The key insights emphasize the importance of building muscle to enhance metabolism and the efficacy of varying intensity in workouts to avoid plateaus in fat burning.