But only once, in one document, out of all those documents, and out of all the times "th" was otherwise used. Once only! That's it. And that was in 1968! All subsequent lines using "th" simply used the typewriter's lower case. The second document to use these was his 'Biography', which may be legit, but which would have been produced after the passage of the FOIA, and may have been typed around Christmas 74/75 or even later. By that time, offices may have begun to use word processors. But again the problem is that those don't match the "th" superscript in the CBS memo. They use a fixed pitch and character width. And the CBS memo has a superscript that looks just like something from MS Word, present day.
Bottom line, as EVERYONE points out at this point, MS Word can almost precisely duplicate the character widths and letter spacing of the CBS memos. All the letters line up, letter by letter, line by line. And the line height can match, as well - not so with and old top end IBM typewriter, or even type-setter.
I put together something that hit the highlights of this, at least as of a day or so ago. And I would find it difficult to believe that anyone looking that over could still have the opinion that the CBS memos are anything but a cheap and obvious fraud.
You are so right.