You are not removing metal just honing it very slightly.
Literally, and by definition, "honing" is removing metal.
You may be qualified to do a stone job on an S&W trigger, but 95% of the people who do this aren't. I've been trained to do it (both free hand and with the jig) and I still decline. Why? Even the guys who assembled S&W revolvers and did trigger jobs at the factory would tell you that they rely on their access to a plastic bin full of hammers, triggers, and sears for when they got it wrong.
For the civilian revolver owner: bad juju.