Seems like nothing is new in fly tying. I have never seen this done anywhere, but it is probably not new.

Anyway, I find that it helps me get a neater head on hackled dry flies. Often, my hackle is not the best and the barbules do not always splay at 90 degrees to the hook shank. In addition, the stems don't always cooperate.

The result is often some errant fibers at the head. You can try to clip them if you have sharp enough pointed scissors, or, worse yet, you can use your hand to "draw back" the fibers. When doing this, and then wrapping thread, you often get an unwanted "swept back" row of barbules.

Anyway, I have had good success using this method. I strip/cut barbules to leave a bare stem about an inch or so above the tie in point. When wrapping, you finish the front hackling with only a bare stem to tie down.

It seems to work well and only takes a few attempts to judge the correct length of hackle barbules to leave for the hackling.