Why are some double-black-diamond runs near-vertical while others are totally flat?

Ask Dr. Flake

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Listen, my son: Just as no two snowflakes are alike, neither are any two mountains, mogul runs, couloirs…ahh, never mind. Essentially, there isn’t a degree-of-pitch benchmark or moguls-per-square-yard checklist that resort managers use when marking maps and trails. According to the guidelines of the Professional Ski Instructors of America, “classifications are relative only within a ski area, not among areas. Managers devise their own sliding scale based on things like weather, average skier ability, narrowness, iciness, bumpiness, and steepness—all relative to the rest of that particular mountain. What’s laughable at Whistler, for example, might, if transported to Wisconsin, scare the gosh-darn bejesus ut of every Packer fan in dairyland.