It's the bowler.
Urethane and revs isn't a bad combo. I know a lefty where I live that averages 230+ and uses a Urethane Purple Nitro. Usually shoots a few 800 and some other scores every year. Very consistent. Being left handed and using urethane I don't seem him have to move much once he gets lined up. That is anywhere he bowls.
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" men lie, women lie, numbers don't "