Pitchers can have more than one type of change-up (off-speed).
The goals are to keep the batters off-balance, thinking (get in their heads), hit your pitch POORLY and have the same pitching wind-up and "motion/speed" for EVERY SINGLE PITCH. (ie. Sell The Pitch)
With my PI experience, the best way to develop the same look/speed on every pitch in to use a sports video APP that allows you to split the screen. This takes time... rinse and repeat... review video... and so-on.
The goals are to keep the batters off-balance, thinking (get in their heads), hit your pitch POORLY and have the same pitching wind-up and "motion/speed" for EVERY SINGLE PITCH. (ie. Sell The Pitch)
With my PI experience, the best way to develop the same look/speed on every pitch in to use a sports video APP that allows you to split the screen. This takes time... rinse and repeat... review video... and so-on.