That fact is another hole in the story and makes the forgery case stronger. The copies of the memos look like Fourth or Fifth Generation copies, using 1970's - 1980's photocopiers.
These memos were supposedly found in Killian's personal files. There was no reason for anything other than the ORIGINAL memo to be in the file - he didn't send them anywhere other than his "CYA File". So, the person who supposedly found the memos, makes his own copies of them using CURRENT photocopying technology - so you have a First Generation Copy using modern technology. Even if you make additional copies of these memos, they all would have been done using modern copiers... there's no reason to have such lousy copies - other than a deliberate attempt to make them look old.
If the copies are so bad shouldn't that have raised questions of authenticity. Why would Dan Rather base a "hit" piece on suspicious copies. Blah! Dan is screwed.