My gear is drilled tip, and I don't use my thumb. Personally, I like my inserts to be very snug as that keeps the ball from squirming around during my delivery. However, when I worked with Belmo, he said he goes larger than normal in the fingers. That way, he can dictate how deep his fingers are in the ball. When he really wants to peel on it, he digs in deeper. From there, he backs off/out as needed.
Now, on the other hand, Cassidy Schaub keeps his thumb in the ball, and I believe Osku may as well. I tried that route and didn't care for it one bit. I have much greater feel without the thumb. I think two-handed preferences are like those for all styles, it's just a matter of finding what works/feels best for you.
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Bowling bad since 1979 with no end in sight
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