Case in point: A month ago, I was fishing in Argentina with guide Katy Melo. All clear creeks, all sight fishing... the trip revolved around catching trout in skinny water... fish that were longer than the water was deep (22-plus-inch browns and rainbows). I had a pair of Costa "Zane" sunglasses with Silver Mirror 580 Glass lenses ($239)... A-list eyewear for one of the best sight fishing meccas in the world. Katy looked at me as if I were wearing the crown jewels. (He had a pair like that, but, sadly, had lost them in the river months earlier.) Since he was the boss and I was following his lead, I offered my pair to Katy, and fished with my backup pair... an adequate polarized tint, but not nearly the same. No matter... Katy was on the fish like a hawk, and we caught many. Suffice it to say, I didn't have the heart to pry them back away from him, and those glasses now live in northern Patagonia, where I am sure they are put to good use every day.