Hans,
I really like that emerger.
Harrop ties one somewhat similar which I used to catch a huge rainbow last summer on the Ranch of the Henry's Fork. However, it had a wet fly hackled collar.

Here is my question:
In all the cripple patterns or emerger patterns in which I am personally familiar, the hint of a trailing shuck is tied in on TOP of the tail fibers. In this fly, you tie the shuck fibers BELOW the tail fibers. Why this deviation from the "norm"?
Thanks,
Byron