Progressing velocity through mechanical change comes from repeated reps over time, constant feedback loops weekly, and small adjustments daily, not some rare gift you were born with. 
 The feedback loop is HOW you actually make the change. Without one, you're leaving your development up to chance. 
 A few lucky guys can throw all fall/winter, roll into spring, never track a thing, and still pick up velo. The other 95% need a real feedback loop to change anything from a mechanical standpoint. Tighten that loop, pair it with individual training, a solid work ethic and you'd be surprised how fast the needle moves.