[shahadi]

Think of the problem as in geometry, then maybe scorpio_rocks explanation will become clear. One height is 10 and the other height is 5 and the distance between the two heights is 2 hex. Draw a line from the 10 height to the top of the 5 height. Extend the line to the imaginary ground. Now, move the 10 height hill back say 5 hex or 250 meters. Note, the angle or slope of the hypotenuse is now at an more open angle than when the 10 height hill was closer say only 3 hex from the 5 hill.

The guys on the top of the 10 height hill can see you or maybe the top of your guys heads at only 3 hex distance. But at 5 hex their LOS is flatter and they can not see your guys.

A picture is truly worth a thousand words.

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