OB isn't an "error" when it's expected -- and the happy surprise is when the throw makes in inbounds.
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You'll need to figure into your "different games" formula, holes will extremely dense rough. I frequently play a course with lots of OB -- but also some holes with very dense rough, where often the result of a bad drive is a pitch-out back to the fairway, with the same scoring result as had the off-fairway area been OB. Sometimes worse, when the escape shot fails.
Perhaps we can identify holes with extreme pin placements, and designate those yet another different game.
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You'll need to figure into your "different games" formula, holes will extremely dense rough. I frequently play a course with lots of OB -- but also some holes with very dense rough, where often the result of a bad drive is a pitch-out back to the fairway, with the same scoring result as had the off-fairway area been OB. Sometimes worse, when the escape shot fails.
Perhaps we can identify holes with extreme pin placements, and designate those yet another different game.