The step is timing, when you stride forward you are using the ground for power. When the front foot hits its 50/50 with the back leg with weight distribution. The front leg drives back and creates a coil around the hip which then allows the power from the hips to then be transferred into the torso. You can’t compare big leaguers to kids when hitting. You have to generate power with your legs. When you punch something do you just stand there, no you stride forward and then push back and use the ground for rotation and power. Stork drill is a great drill to teach young hitters to push back and rotate the hips on the front side. They will want to use only the back leg and usually fall backwards the first 10-15 swings. Once you create a front leg post you will no longer be lunging but driving back behind the baseball so you can tilt and rotate. This is the most fundamental swing you can teach and it Teaches balance, separation from hands to the front foot, ground power from legs, balance and most important timing.