I don't think there is any specific pattern that promotes playing 6th or 7th arrow more than others. By that time it all depends on how they break down.
Example: Look at Robert Smith lofting the caps on the SHARK in Vernon Hills last season.
Also, lofting the gutter caps is nothing unusual at the collegiate level where there are 8+ games of high(er) rev players on them.
And the deepest I've seen someone successfully play is lofting about 30. I mean hitting 30 on the fly, 25 feet down the lane, and out to 10-15 at the breakpoint. At that point it isn't about how many revs but rather how far can you loft the ball.
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Michael Nelson
Northern Illinois University Bowling