I shimmied along a narrow ledge above a slot canyon somewhere in Anza Borrego State Park. At some point I began to vividly imagine what it might be like to slip and tumble into the narrow void. A trickle of sand and pebbles skittered down from under my feet. Looking back the way I came, I tried to judge the point of diminishing risk/reward. It didn’t look promising, but the alternative was a two-mile detour. Should I go for it?