I guess I used to. Even read the one for my first couple cars, front to back. Now I just hang onto them for reference.....unless they're for something new that I don't have one of already.
I have never sharpened the bottom of a chain. Even my old worn out chains are still sharp on the bottom.
Is this like sharpening both sides of the cutters? That way it is imposable to put the chain on backwards. Why not sharpen the bottom too, then you can just put it on any way you want.