I'll try it, if only to get a better understanding of the materials I'm working with! I'm only starting to mess with these flies (Kentucky isn't exactly a hotbed of salmonid activity) so it's all new to me.
I have done this before and it works well. On some of the feathers you will need to soak them in a cup of water before you tie with them because the stem is too stiff if you don't to hackle. They make for good looking flies.
Thank you for finding this and posting it here! I have had several people ask me about burning feathers and I have been dreading all of the typing it would take to explain the process. Now I can just link people to this thread.
The only thing I will add to what the fellow has told you is that this also works with Marabou and ostrich feathers and they are much like mallard flank in that you need not work them in the bleach for very long at all.