I have to admit that I don’t. I take it for granted that my tying skills will produce a fish taking, durable fly. I have not worried about durability for decades. As I write this I dont know if thats a good or bad thing.
I am guessing here, but I would say close to 90% of my fishing is done dead drifted with weight near the bottom of the river. When fishing this zone one must expect to lose flys to dead falls, rocks and any other debris laying in wait to snag their offerings. Sad to say my unofficial motto has been, "Why spend 15 minutes on a fly when i will probably lose it in 5 minutes on the river?". When I would say that to myself I was referring to the construction of the pattern rather than the durability. I wanted to stick to basic, easy patterns. When I first learned to tie a Kauffman Stone Nymph it took me 30 minutes to tie it. Yeah, I lost it to a snag in the river the very first drift. Went back to a more basic 5 minute Stone pattern and did well with it.
I would guess 10% of the time I throw Streamers or swing a couple Soft Hackles. In my opinion it is in this area that durability plays a big part. If you have ever been on a river that the trout were chasing emerging caddis out of the water, then you know how deadly a pair of Flymphs can be when swung down and across. The Gunnison prior to her surge in popularity use to be that river for me. A pair of Muskrat Flymphs could easily account for 100 fish in a day. Mind you, most of the fish were small. I would say 10 inchers were the average, and I think I am being generous in my guess. Replace one of the Flymphs with a Woolly Bugger and the average size would jump to 14 inches, but the numbers went down. It was a typical quality VS quantity issue. I have to admit it is a dilemma I don’t mind having.
Ok, this is the paragraph where I beat my fists against my chest and tell you how durable my patterns are. 100 fish between two flies? Why folks, my patterns and I must be the greatest things to hit water since Moses parted the Red Sea! OK, that was a little sarcastic, but I do feel it was a way for me to determine that my patterns were tied with quality and care. In other words durable. Maybe not as durable as with tiers in past generations, but good enough for me.
So, where do you as a tier place the importance of durability in your patterns? Perhaps, like me, you have taken it for granted and no longer think about it. There is no wrong answer.
Lance (gingerdun), thank you for making me think at 2:45 AM!

Now the part of the post that I will dedicate to confessions. Here it comes. Ready?
A couple times a year I have a pattern fall apart due to ………Operator Error! There I said it! Once in a while I am embarrassed to discover that I am capable of tying subpar Flymphs. Yes, I hope I can be forgiven, and I completely understand that if you ever invite me in your home, you make me enter through the back door.
