Had a feeling that stories of unreliablity had to be overstated. In the bit about snodgrass hill it’s told that soldiers urinated on the barrels to cool them down, to get to this point they would have been repeatedly fired with no faults.
I've seen the documentary you've mentioned. Personally I'm a little doubtful of that story, as I've never read it or heard it anywhere else. It sounds more like something out of WW2, but there's chance it happened.
As for stories of unreliability in guns, it goes back to context, and soldiers not knowing their weapons. Take the WW1 vintage Chauchat for example, EVERY book and author out there is adamant they were pieces of junk and without question the worst gun ever built (and that is exactly how most authors describe it). But that's quite incorrect because of context. The French didn't have many problems out of them, and kept issuing them alongside newer and better designs till WW2. Were they idiots? No, the gun worked. Its the American version built in France in .30-06 that had problems, bad chamber measurements, bad bore measurements, bad training, and not the best designed box magazine, that gun was cussed over and over, and almost every author out there is adamant the
all Chauchats were junk because of mostly American complaints, even though France, and more than a few other countries kept them on hand and used them in WW2. Look up Forgotten Weapons on YouTube, I'd say they've debunked that myth pretty well, with a French Chauchat and even an ultra-rare American contract Chauchat with the chamber and bore issues fixed, and both kept firing and firing without issue. Its just a quirky gun, kinda like the British WW2 Sten.
I think the Colt M1855 has suffered a similar fate, with the Berdan guys cussing it, and a modern fear of chain-fires, the poor gun gets a bad rap even though the majority of folks back then had no problem with it.