Have a high school kid come in and let him throw some of his good stuff.
They may be focusing on the machine, which gives them some opportunity to guess where the ball is going to be.
If a high school kid comes in and is use to messing with batters he change things up and even point out how they might have hit that thing.
He can then encourage them to swing and you might double the number of times at bat practicing in one session.
Say from 10 opportunities to 20.
Nice! I have a highschool pitcher in mind now!
When I was a little leaguer our coach brought in a high schooler to pitch to us but, our catcher couldn’t handle his pitches. The coach came in but had a hard time with the crouch position so he pulled a cinder block behind the plate to sit on. Well, a foul tip and a pop hop caught his family jewels, “between a brick and a hard place”. He was taken away in an ambulance and didn’t return till midseason.