Here is my favorite one from that article...

http://www.flyline.com/tips_trivia/myths_legends_lies/

"You must match the color of the prey. What a crock. Trout see every color we do, plus they can see infra red and ultra violet. When we see a green caddis larvae, we are seeing an object that is absorbing all the visible wavelengths of light except blue through yellow. These colors are reflected in a blend of light that appears as green to the human eye.

What if this caddis is also reflecting ultra violet? It'll still look green to us because we can't see UV. To the trout who can see into the ultra violet spectrum, the caddis will look something far different from green.

It is well known that many patterns, such as Bob Quigley's para nymph, work better when tied in purple rather than the PMD hatch matching yellowish green. To our eyes the imitation looks nothing like the real thing, however, the infra red reflecting qualities of the purple fly are better at imitating the natural as the trout perceives it. And that's what counts.

Out of a laboratory we have no way of knowing how trout perceive a bug. Luckily, it doesn't matter. Trout don't care if the fly contains the wrong color. Blend lots of colors into your dubbing . . . as long as the right color is present, most fish selectively discriminate against the wrong colors and take the bug. Whitlock's "bright dot" flies are a perfect example of this."

As far as the tippet goes, I think, and take it for what it's worth that at times on streams where fish are pressured that being able to drift nymphs more realistically, while they are attached to the end of a fly rod, which in fact is stationary, that a slight change in the diameter of tippet will draw one or two more takes than the larger one. Is it the difference between success and none, surely not.

About the heavy leader attached to the flies referenced in the article, George Harvey did a similar experiment with inserting heavy line through a beetle, when inserted through the beetle, the trout did not hesitate to take the fly. However, when he put the same beetle on the end of his tippet, he got nothing but refusals. This lead him to the idea of the "slack leader"

The combination of the smaller diameter tippet, distance between the indicator, weight of the fly, available light, reflection of light on the leader and a host of other things combined to make the fish take my nymphs. Do I think that I could have taken the same amount of fish on 5X? Most likely not, or I would have not made the change.