Well, yes, assuming they came through, it probably would. (My head is still spinning from his work for IBM those "13 years in the 70s.")
I know the 70's was a long decade but 13 years is something. That alone convinces me the guy's a liar or an embellisher.
Here's a stupid question. Is there nobody anywhere that can investigate what kind of typewriters the TANG used in the early 70's? Is there any way to determine whether the PO box is legit? It would seem to be these two facts would drive the final nail into CBS and Rather's coffin.