I had a similar problem - huge body (6'2"), fast feet, planting my slide and bending over to catch up with the swing.
Slowing footwork down was one remedy, but the bending was hard to come by. I would not bend my knee, still with the planting tendency.
A fellow bowler who watched me play suggested one day that I should try a half-sitting position right from the adress position. I tried this and it was a start to improve my overall delivery. I also learned that I had to be careful not to start and end up in a crouched position, but the "duck walk" ahd two benefits:
a) I was able to bend my sliding foot's knee for a real slide (Finally!)
b) my body's CG was shifted back, preventing the bent upper body
The latter was achived through conscious effort to keep the shoulders square and upper body upright. Looked a bit funny for a while, and I got several comments about this wacky style.
But once I got the timing and slide in synch, I gradually started with a more upright starting position, which is today "normal", and I have learned thorugh this detour how to lower during the approach, bend the knee and actually slide. I even got positive comments about the huge slide I make nowadays... But it was along process, probably 9 months.
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DizzyFugu - Reporting from Germany
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