when the removal of 0 lines isn't documented anywhere, I think it is legitimate to assume that forbidding them was an unwanted spec glitch.
as far as I remember the discussions of those days, the special case "a single 0 on a line" was intended to be explicitly allowed, because some people use it as a separator
as far as I remember the discussions of those days, the special case "a single 0 on a line" was intended to be explicitly allowed, because some people use it as a separator