at least on some firearms like the older rimfires I am talking about, cutting through the hardened surface will absolutely make for an unsafe trigger. What happens is the sear engagements wear out very quickly once you get into the softer steels. It's hard to tell on those old dogs. You hone the sear, you takes your chances. Some years back there was a really neat Italian copy of an 1803 Harpers Ferry flintlock musket (such as used by the Lewis & Clark expedition). Only problem was the lock was very stiff with a high trigger pull. Word got around that honing/polishing the lock would cause it to fail after less than a dozen shots as the parts had the barest of surface hardening.
To be honest, my Shadow is just for informal shooting, so I am pretty well satisified with the stock trigger. Not that I am easily pleased. Just that I take it for what it is - a hunting rifle. Believe me, it has a much better trigger than most off the shelf rimfires nowadays. If I want a good trigger I reach for my Diana 75. That's about the best trigger I own. But, of course, it's not a field gun.
What, me worry???