For an advance player, Example if you are a wide receiver, we will jump right into adjustments that happen post-snap when the coverage changes due to disguise. Learning to recognize it and then knowing how that will influence the route.
Example of you are a wide receiver, We will work on being Quarterback friendly coming out of routes to make passing windows more appealing to Quarterbacks while making ourselves easy targets. We will also work on blocking angles, how to approach a block as well as engaging and re-engaging to prevent holding penalties.
Example, If you are a wide receiver, we will focus on the fine details of footwork at the top of each route, footwork for each route changes on the angle and the depth of that route, clean footwork leads to separation, not speed. My older and more experienced players will be expected to not only master the route depth, the ability to avoid press and re-route but also the footwork in and out of breaks which is the hardest thing to do.
Mastering body control is the final phase of great receiver play, once you’ve learned how to identify coverage, avoid press and re-routing, understand windows and spacing, making yourself Quarterback friendly, blocking angles and approach, footwork off of releases, getting in and out of breaks etc, then it just comes down to perfecting the flow of your body. Maintaining balance as well as smooth transitions of speed through acceleration and deceleration all comes down to body control which is gained by tons of reps and building muscle memory, by doing it the right way.