many stacked wing tiers will tie two versions, one for the shadow box, and one which can be used if requested. The shadow box variety is usually all original materials which were used back in the 1800's when many of these were developed. The 'fishing variety' usually have reliable substitutes for the more expensive feathers in the shadow box flies. A lot of time goes into tying these flies.
I recently tied my first Jock Scott, all told i was sat a the vise for about 3 hours, and it ended up looking like it had already been fished!
take a gander
I think a few more years of practice will be required before i get to the shadow box quality. However, this one being my first, i will box it as a memory of where i started!