I use white Z-Lon for the wings in many of my dry flies, Byron, and I'm not sure I could tell the difference from your Widow's Web wings. I can tie wings of Z-Lon on 6 flies in the time it would take me to tie just one fly's wing of calf tail, and they have all the visibility I need to catch plenty of trout. And, we all know what a pain floss can sometimes be.

So, for me, I'd say your modifications make a fly that is superior to the original. Not knocking the original...they were undoubtedly tied with materials that were available at the time.