An interesting approach, and I agree, probably not coincidental.
The author touches on another aspect, the pitcher's height, which also might have another influence. A taller pitcher with a longer stride (and longer arms) also brings that release point even closer to the batter, giving just that much less time to adjust. If a normal release point is about 55 feet from home plate (just a guess), releasing the ball just 1 foot closer has the same effect in terms of time reaching home plate as adding 1 full mph to a fastball. A freakishly taller pitcher like Fairbanks or Glasnow might be about to exploit that to the point of getting up to 2 feet closer, which is like adding 2 full MPH to a fastball. And we are talking about guys who routinely hit 97 mph (Glasnow) and 100mph (Fairbanks) to begin with....