When I tie common mayfly nymphs (which 90% of the time are PTs or GRHEs
or some combination or variation), I usually tie a single strand of
pearl Flashabou over the wingcase. I picked this up from Bruce Hopper.
It works great. No epoxy -- just a bare strand. It usually gets broken
after the first hookup, but I keep fishing with it and that doesn't seem
to matter.

Maybe the Flashabou doesn't matter. I think it does, but flyfishing can
be an exercise in self deception.

I don't think it's imitating a natural feature so much as drawing the
trout's attention in a fairly subtle way. Some insects have iridescent
wingcases, but I can't say I've ever seen a natural with one. Maybe I'm
not looking closely enough.

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