I wouldn't say that weight holes have no effect, but they become third in importance with regards to layouts...
or possibly better way of saying it is that weight hole have less of an effect in asymmetrical core balls than in symmetrical core balls.
For asymmetrical cores, pin placement has the greatest effect, followed by the MB placement, then weight hole.
However...coverstock and surface prep is the #1 determining factor in any ball.
S^2
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