45 degrees to the lane.. yes. 45 degrees to his body... no.
Run the video, and stop it at his release point. You will see his shoulders are opened to about 30 degrees, and his hand is at about 60 degrees on the ball. How the ball hits the lane isn't my point, it is where his body is in relation to the ball in his hand at release.
I also see several other things he could work on, that would directly help with the ball position, and slide.
1. he dips his shoulder alot throughout the swing
2. he never squares his shoulders up, even after his release, his left shoulder is far out in front of the throwing shoulder
3. his body is constantly open to the lane.
4. he gets down thru his approach, but only at the waist, he needs to get lower with his knees, and keep the upper body a bit more solid.
Any of these, and the combination of all these, will cause his stiff front leg and awkward trail leg swing. The slide is a product of the approach. Fix the approach, and the slide will fall more into place... not the other way around. Once the approach is better, tweaking at the foul line will be more productive.
What I see on the video, is pretty typical of what I see from alot of younger bowlers.... heck.. from a lot of bowlers period. They have basically learned to throw the ball on their own, but the fundamentals are a little flawed.
