I like to fish a Royal Wulff. Big ones. No, I'm serious, don't laugh. Well, maybe you're not, but I can't tell you how often I've been mocked for doing so. If I'm prospecting riffles, having a tough day figuring out what I the fish are taking, or generally don't have another idea in mind, I'll often tie on this time proven pattern and go to work. I know plenty of other anglers who don't even carry this pattern and most certainly wouldn't be caught fishing it. The reasons always seem to be the same: it is old fashioned, non-specific (though what attractor patterns aren't) or -- more often -- it is taken as a sign of a lack of penchant for proper study and deduction on the stream. Oh, and it's not very cool.
As far as I'm concerned, this is all nonsense. Like many other fly patterns which have fallen out of favor with time, the Royal Wulff has -- in my opinion -- simply fallen victim to being unexciting. So many anglers are busy looking for the hot, new, trendy pattern that they've abandoned patterns that have survived for over a hundred years, presumably laboring under the delusion that fly tiers of the entire 20th century and before were completely devoid of imagination and forced to do little more than tie the same few dozen patterns over and over again.
Me? I'm interested in what works, and recognize that these patterns survived for so long because they do. As such, I'll often make it a point to carry these classic and sometimes rarely used patterns, laboring under my own delusion that the fish in the stream I'm stalking never see these flies anymore.
As I was pondering this thought recently, I stumbled upon this post (link now defunct) by Michael Gracie, in which he recounts his 10 greatest days on the water and the flies that made those days what they were. Given what you've read here thus far, you likely won't be surprised to learn that they were all classic, run-of-the-mill patterns, but you might have been if I hadn't set the stage before mentioning Michael's post.
Truth be told, most of the patterns in Michael's list are patterns that have stood the test of time well enough to still have a home in most anglers' boxes, but none of them are the latest and greatest fly of the day.