Actually, having thought about it a bit more, artificial grain seems like a perfectly acceptable way to attempt to restore the feel of a film, if you feel it's been damaged by excessive DNR.

The problem, in my opinion, is that DNR really isn't something I'd say is a big problem with these films. Excessive sharpening, sure, crushed blacks, definitely, but DNR? I don't really think so.

As for adding hairs and scratches, I'm just plain against that. People who want hairs on their film can empty their vaccum cleaner bags on their projectors, and those who don't don't have to. It seems like a bad thing to have in the source image.