It is interesting that you quote Jim Stangowitz from http://www.uky.edu/~agrdanny/flyfish/dryfly.htm from the Flyfish@ page under "How To":

http://www.uky.edu/~agrdanny/flyfish/main.htm

I was one of the early members of Flyfish@ when it was the only place on the internet to discuss fly fishing. This was well before the WWW.

I volunteered to write the original FAQ page for FF@ back in the 1990's. Since I wrote the original FAQ's, I have my own section on the Flyfish@ page under "Henry's FAQs". You will see that my FAQ's precede Jim's of 1997.

http://www.uky.edu/~agrdanny/flyfish/hnrymenu.htm

If you are interested, my Dry Fly FAQ is at:

http://www.uky.edu/~agrdanny/flyfish/faq/faq-3.htm

Jim Stangowitz was a friend of mine. We were on Flyfish@ back in the "old days". He asked me to look over some of his writing but not this particular one, otherwise I would have told him that I thought he was wrong about selectivity. Unfortunately, Jim passed away last year of a heart attack.

Although I did not contribute to Jim's FAQ you quoted, I did contributed to 3 of the FAQs under the "How To FAQ's" including Jim's other FAQ on "Beginners Guide to Rod, Reels, and Lines". You can see that Jim credited me under his Conclusion Section

http://www.uky.edu/~agrdanny/flyfish/newfaq.htm

I also contributed to the "processing Fly Tying Material at Home" by Bob Petti

http://www.uky.edu/~agrdanny/flyfish/petti.htm

and I contributed to the Warm Water FAQ by Buck Hall.

http://www.uky.edu/~agrdanny/flyfish/wwfaq.htm

Jim had his perspective on fly fishing, but I believe he was wrong on this particular aspect of selectivity.