If you plan on doing any changes. Take a video camera with you. You need to see what you are doing.

I know a lot of bowlers that think they change something yet they fall right back to their original style. Also you nned to be positive and patient! Be prepared that what ever you are tyring to change is NOT going to happen after a couple of games. You are trying to develop something that is going against what your muscles and mind are currently doing.

Good luck.

I struggle with this very same issue.  I've had the opportunity to work with Ron Hoppe through an IAB Bootcamp a few years ago and things are better but I still have problems with this.

I've attributed my issue to my backswing going higher than what my flexibility will allow.  Everything is aligned through my backswing until a certain point where my shoulder will no longer rotate in that direction and due to the momentum it then slides to the left.  What I need to work on is getting my shoulders to open up more along with trying to get my hand on the inside of the ball instead of behind. (like many of the pros do)

I'm not a coach, these are just things about my experience and my own physical abilities (or lack thereof).

Thank you everyone for your feedback. The greatest thing about this game is the challenge of getting better. I felt as though I hit a peak in my game. It was at that point I realized that I could continue to do the same things with the same results, or I could study the game and try to alter mine to gain more consistency. I always have a video with me and take lots of film. It is amazing how hard it is to change muscle memory.

Trash heap: You are exactly right, it takes a lot of patience and positive thoughts. It can be hard to remain positive when going through changes as often times your scores suffer. Patience is key, it takes thousands of shots to change muscle memory. I remain positive because I love the game and the challenge it brings.

ImBackInTheGame: Your comment is spot on. I am the farthest thing from flexible, thus it has always amazed me at how high my backswing gets. I just went back and looked at recent film. When the ball is at the level of my head, it covers it, indicating that the swing was straight. However, as you stated, once my backswing gets above my head, it slides to the left. Focusing on a more relaxed, less muscled backswing will most likely fix this issue! Thank you!