I think it's considered one, but I have a nerve pinching problem that requires me to have reverse pitch, and consequently I have to grip the ball to hold onto it. I just don't feel comfortable not squeezing it though. If it works for you though, it really can't be wrong. There are pros with flawed games, but as long as they're accurate and they score, does it matter? I'm not saying that as an excuse, but you just have to find what works for you.
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I know Kung Fu!
I am the one, the one that will bring balance. All the pins shall be destroyed!