You already mentioned one part of the equation: a consistent game. Only when you can repeat a shot with control over speed and hand position you can IMHO make adjustments or an educated guess about what to try.
That said, you need to have a keen eye on the ball's reaction (skid/hook/roll), and have an idea which lane factors might hamper it. Next part of the puzzle is to know which measures might help in which way: moving your feet, changing the ball, changing speed, revs, breakpoint, and the like. These are all factors you can affect with your decisions.
Choose your weapons and try - but there's no easy answer to your problem.
DizzyFugu - Reporting from Germany
2010/11 Benrather BC Club Champion
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