Obviously, cutting to the left or right depends on which side I’m keeping, since ignoring the kerf kind of makes the whole fine line thing moot. That aside, there is no real on or beside the line for, say, a point three Pentel pencil or a sharp knife. No?
Ninety-nine percent of what I do is with a point five mechanical pencil. I can’t remember the last time I picked up a regular pencil.