I have no idea of the name(s) of the ExSPURT who decided that the traditional winged wet fly represented a sunken dun. Nor do I have any idea if that same fly represents an emerger, a malformed dun, a cripple or any other stage or injured insect. Has anyone asked Mr. trout and what has he said? To make a 'statement' with any type of surety is the height of egotism and silliness. It is no more correct then for me to opine, when I say that, a trout came up and took a cigarette butt that I had just thrown into the West Branch Del. from the old Hale's Eddy Bridge because it looked like a floating worm. I have absolutely no idea what that trout was thinking.
View one of the excelllent 'underwater' videos available. You'll see that trout try to ingest a lot of stuff other then food. Now, I'll go back to my opinion that I stated in an earlier post, and it's just that. Compared to many sub-surface flies, I'm excluding nymphs, traditional winged wet flies are not easy and take longer to tie. There are lots of new materials that have displaced natural materials too. Traditional wets are also somewhat difficult to fish. Those are the major reasons for their fall from grace. And I'll reiterate: before the turn of the 19th century, trout in the northeast were nearly decimated due to man's effect on the environment and especially fishing. Yes, bait was often used . However, the chief culprit in the fishing destruction of trout were flies and the flies used - winged wets!

Allan