Son not comfortable with "new" arm slot....yet. THOUGHTS?

So today my son tried his “new” arm slot witch is low 3/4 from what used to be High 3/4. He said that it didn’t feel comfortable at all and that he kept having to think about what he was doing and half the throws he didn’t even know if he was in the new slot. He wanted to try the new slot because he feels it will give him more movement and more velocity witch it may. SO should I tell him to keep trying it until it’s comfortable or should I tell him just to stay with the original slot that he’s comfortable with and that’s natural?? I just think he needs to decide on something so that way he can begin his throwing program and work on things that need to be worked on for the next season. SOO… Thoughts??

At this point I would think he should go with the slot he currently has developed. The high 3/4. He will not likely throw as hard in the lower slot and he will probably lose some of the downward movement on his curve. While fastball movement is nice it is also good to have a straighter fastball you can easily get strikes called with. He can develop a two seam or cutter later for fastball movement from the high 3/4 slot later.

Get him to practice his new arm slot in the mirror get him to use his elbow and wrist working together in his throw have him practice in the mirror.