This reminds me of a story. Michael Bastian had all the girls on the Chinese National team carry 1/2 of a softball, marked you must hit the inside of the ball. When he worked with my dd on slapping I made a softball like this and she has it hanging of her bag as a reminder. Since I like to try things. I was able to put it on a T and had my dd hit it. You can hit a very good line drive only hitting 1/2 a softball. The swing that doesn't hit the inside part of the ball, looks like a wounded duck as it flys off the T. Many ways to practice this. The two T drill , when you line up two T's and practice hitting the ball thru the ball on the second T. That will teach you to hit the ball correctly.
Discouraging early uncocking of the wrists and casting like this is fine but balls do get hit to left field. Can't do that hitting the inside half/the half facing 3B. No doubt you understand this-speaking to some of those who don't post.