I think this learning process occurs in many spheres of our lives as we grow in knowledge. Differences in knurling or styles of crow’s feet (↑) bother me less now. I have discovered that there is no magic formula for what is a legitimate Fairbairn-Sykes of any style. Robert Wilkinson-Latham quoted Shop foreman Charlie Rose saying: “there was a war going on.” I have seen blades ground crooked, sheaths made over a ½ inch too long, handles with casting flaws, knurling that was botched, guards on upside down, a dozen varieties of top nuts, inspection stamps running off the edge of the guards or double stamped, and all sorts of anomalies. So what? This is what makes collecting interesting. What is more valuable a book of regular postage stamps or one stamp incorrectly printed? Literally hundreds of thousands of 3rd pattern knives were produced. Which is more valuable? The thousands of them with identical stamping or the oddball stamped A2, or A COY etc.
So, some of the folktales, like those about the “correct” top nut marks, or the “true” purpose of the triangle grind near the guard, are useless bits of folly. Blades got broken and replaced. This required removing the top nut. The “mysterious” triangle grind simply tapers the blade to allow it to enter the opening in the guard. There was no magical clamp used to “draw the blades.” Wire is drawn, blades are either forged or stamped out. What is interesting is that many of the older folktales have proven true. For example the one about 1st pattern knives with 3 inch guards, Stephens had it right. The stories of commando daggers made from bayonets is also true and “WSC” stamped on certain blades is correct, Windrum had it right, (despite what other websites and forums might say). So it is erroneous to say that all folktales are untrue. It would also be incorrect to say they are all true. Only with time and familiarity, research and study, can you begin to sort the wheat from the chaff. Just do not get caught up in the minutia that obscures the bigger picture. And just because you have not seen it does not make it a fake.