I was just wondering what exactly is the purpose of the wings, for say a dee style or wings that are married, is it for a certain profile or what? it doesn't seem that these style wings would have much movement in the water. the reason i am asking is because a while ago i tied a GP fly and just laid a single small mallard feather centered over top of the body. it looked o.k. but didn't know if maybe it was defeating the purpose of a certain wing.