Robs experience accepted of course, I have been a range officer for 26 years in pistol, rifle and shotgun competition, bullseye to Uspsa, I have seen many 1911 failures, some inherent to the manufacturer and most not. Most common.
1) reloaded ammo.
2) non ball ammo.
3) operator error, ( limp wristing, small person shooting, with not enough strength to back it up )
4) home smithing and modifications, to springs and such.
Every failure you have read about, I have witnessed.
1) collet bushing fracture and failing. Poor design for reliability.
2) double charge that blows the magazine out, and blows the grips off. Operator error.
3) elliason sight roll pin breakage on Gold cups. Bad choice of parts.
4) on the early Kimber officers models, the barrel bushing was too thin where it holds the spring plunger, and the ears would
break off, and the spring and plunger would shoot downrange, They did fix it. Poor design to start.
5) sear and disconnector failure, Read: full auto. Normally, home made trigger jobs gone wrong, and gold cups, misassembly.
Nearly lost a friend to that one, walked out on the range after reassembling his pistol, and dropped the slide on a full mag, with it in his strong hand, and it went FA, 3 rounds of hardball in his left arm, and he was lucky. Because of his experience, I never drop the slide on a 1911 without my finger on the trigger, holding it back and with both hands around the grip just in case. Read Peglegs post, I did learn from my friends experience.
6) match fitting of the barrel and slide, needs to be broken in, to be reliable, and just like race cars, match guns need to be fed race ammo, tailored to the gun, expect malfunctions until these two criteria meet. I had a friend who brought me a Les Bauer Comanche, that Worked when it was shot, but was fit so tight you could not operate it by hand, when a round was chambered. But when loaded, it shot and fed.
I own 9, 1911's with 2 on the build, all work with wadcutter ammunition, except the .22rf of course, and the .22rf are more finicky. So I do own and shoot them, like them very much, but if I took one of Robs classes, it would be hardball all the way. And sorry to say, I would take it with a glock probably. As that is my go to, no BS pistols, more ammo, and unarguable track record.
But that spare Colt slide and a guy on AR15dotcom with a .460 rowland conversion has got me interested, not to mention a friend gave me a Delta elite barrel, so a new Sti slide in .40 with the full length slide with no dust cuts sounds interesting.