Azus is correct, what happens is the bowtie is lowered on a lower pin layout and it greatly increases the chance of a higher track player to clip the fingers and/or thumb.
You can still use the layout though, as a weight hole can be used to raise the bowtie as needed. I would suggest if you experiment use the ball first and to see where your track is and then add a weight if needed to make legal or move your bowtie.
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Just another aspiring junior bowler who is just starting to get there.