You track between your fingers and thumb.
The drilling has the pin almost in line with thumb, somewhat strange looking

I'm not 100% sure how you throw it to get it that way, but I am guessing you completely turn the ball on the side where the finger holes and thumb hole are rolling over top of one another. I've always wondered and no one has been able to give me a good definition.
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Ahhh Disco Biscuits!