Every bowler has eyes.
So, as competitors we should all be able to observe what others are doing and make proper determinations on where the line might be and what type of equipment to use, whether it be league or tournament play.
When it comes to competition, to each his own--I don't feel the need to coach competitors, and if so asked, I just say that everyone has their own game and style, and politely suggest to them to watch what others are doing.
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Regards,
BowlingWolf