Depending on who it is, where you are, and what the league bowlers want, the Kegel pattern is definitely easier.
However, the bowlers will improve in the longrun if they are bowling on tougher, sport-compliant patterns more often. I think it's a great idea for a center to run one of the middle length PBA patterns as the "House" Shot. (Chameleon/Viper)
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Righty
High rev rate (400-450 rpm)
Semi-high speed (16-17 mph)
Book average: 202
For a game based on the principles of science and math, bowling sure does have a bad habit of being illogical.