Dave, I use Lee's method for sharpening my hand saws. I use a 30 degree angle on the file in both directions (if that makes sense). I have a tendency to over set, at which time I take a light swipe with a stone on the outside of the teeth to shine them and take some set out, or if one side is set more than another. I find this will fine tune the set to what works. You might try this on the over set saw you created, if the stone will cut the hardened teeth? A warning, not your nice water stones, a cheap oil stone with two grits will do just fine.

Tim