You might think of this as a balance thing. A "normal" player, regerdless of his style which might be termed stroker, tweener or cranker, has a balance of revs and speed. There is a positive correlation between revs and speed, a kind of "golden path" which allows the ball to work properly.
Once one of the 2 elements becomes a superior influence, a player can be termed "speed dominant" or "rev dominant". Speed dominant players have difficulties to make the ball finish well (it just has no time to work on the lane and use physics to exploit the core's dynamics), while rev dominant players rather fight with the ball to keep it on the lane or to break too early. Mind that "rev dominant" does not necessarily come from ulra-high RPMs - it can also be the result or relatively slow ball speed (and the same counts on the speed side, just the other way around).
Both can be successful, and with drillings, surface changes and other tricks the "golden path" can be widened enough to come closer to an effective speed/revs ratio.
Nevertheless, there is no hard definition what a "good" speed/revs ratio is, since there are many variables in the background which affect effective bowling.
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DizzyFugu - Reporting from Germany
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