This fly was allegedly invented by Edward R. Hewitt in an attempt to catch some of the trout he saw rising to large butterflies. He called it "The Neversink Skater" in honor of his Neversink River. He claimed that because of the over-sized hackle, more line (about 40 feet) is needed to cast the fly -especially on a windy day. Also, he said that proper sized hackles for the fly are hard to find. they need to be very long & very fine.
Hewitt said that the proper way to fish this fly is to cast it over trout & "skate", or pull, it across the surface. However, you can't pull it too fast or it won't work. It can have a tendency to put trout down & spook them if moved too fast. No movement at all doesn't deem to work very well either. You have to find the right speed to skate the fly to get it to work.
This fly can be very effective when there is no hatch occurring It seems to be even more effective when the larger mayflies have been around on the water, say, late May to early June. The claims that Hewitt put on this fly would make think it's one of the best ever made. So why don't we hear more about it? Because it does have some draw backs.
The long hackle quickly becomes water-logged & is hard to dry. So you have to change flies often. Also, only larger trout seem to rise to it - in the 12 inch + size. Alas, you'll miss a lot of fishing action based on this. Another draw back is that because it takes a longer line to cast well, it can be tiring to cast this fly all day long.
Hewitt believed that a spider tied as a bi-visable was best (brown hackle with a white hackle front). He also found it effective in cream & grizzly, too. It's to be tied on a smaller dry fly hook than you'd think, about size 12. The hackles, when wound around the hook are to be about 2 inches in diameter or longer if possible.
John Atherton goes into a lot of detail about these flies in his book "the Fly & The Fish", devoting an entire chapter on it.
So the next time you want to try a different attractor dry fly, consider giving this one a try.