When looks aren't everything

Fly fishing is a straightforward pursuit. If the cast and presentation are good enough you do not need to vary your fly too much between maybe half a dozen designs of various sizes and weights.

So why do my fly boxes tell a different story? Inside are scores of different styles and hues yet there are days when not one pattern among all of them seems right. The problem is that fly designs are supposed to focus on the habits of the fish but in fly selection irrational human behaviour is still so often the dominant influence.