In my experience, and as someone who has technically been a professional copy editor before (in the sense that I got paid by someone to perform line/copy editing of some material or other, but definitely not who or what you would think if I only said I used to be a copy editor), the uses of "not only, but also" that didn't have anything wrong with them (or didn't deviate from convention, if you like) were in the minority by far. Assuming people in the last few years haven't all become suddenly interested in that particular construction and skilled in its use, the presence of an improperly implemented NOBA should remain vaguely reliable as an indicator of authenticity :D