Having never tied the IBD, i had to look up the pattern.
This one struck me as interesting, and i had the materials to tie it.
Only differences from the video below is the use of a Kamasan B170 hook, size 12 and i stripped half the dun hen hackle. Everything else is per the pattern and tied in exactly as the video.
Hope you fellas like it. For me, it looks like it will work a treat on local PA streams, and maybe even a size or two smaller, but those were the smallest hooks i had.
The video is from Hans Weilenmann