From what I see the best analogy would be to compare Sam to a young gifted golfer who starts receiving professional instruction/coaching.
Before you know it the young guy has his head so wrapped up in what he was instructed to do. That he subconsciously fights the very mechanics that made him a good player to begin with.
He becomes mechanical and deliberate. And in the process suffers from confidence issues and mental lapses that never occurred before he stated receiving professional coaching. For the simple fact he is being asked to do something that though not technically incorrect. Doesn’t apply to that one specific individual.
Basically Sam is playing with a tight ass. You don’t even have to watch him play. Just watch him on the sidelines. His eyes constantly swinging right to left, which is by the way a common indicator of an individual attempting to deal with inner conflict. You can tell you he is trying to hard to accomplish the task at hand, instead of just letting it happen organically.
I have seen similar shit like this for 40 years in youth tennis, golf, baseball and football when the kid makes the jump to the collegiate level. Great coaching can see this, and can adjust their input accordingly. Bad coaching believe it to be the pupil.