I believe that a both / and benefits a hitter more than an either / or approach. It is clear that this website structures their arguments around the latter, as echoed by this statement: "becoming a great hitter" and using Erik's Instructo-Swing "will [...]not work in conjunction." What Batspeed.com supporters sometimes overlook, though, is that the two polarities can "work together."
This becomes apparent when a Batspeed.com disciple refutes the aforementioned logic by noting that one father's teenage "girl has decided to buy into jack mankin's swing," although he has "her swinging on the instucto swing and everyting looks fine." Essentially, the customer's daughter is navigating through a system that might help her reach her potential, and a device already proven to work for her. How, then, can one say that a singular method trumps all others?
Ultimately, all players usually care about is their ability to hit for power consistently; hence, their trek for self-betterment is neither one hundred precent correct, or "100% incorrect."
Just some keen observations,
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