Reply #84: That's easy

[juajen]

Because something new is not always used by a typist, especially if she is used to doing it the other way. This easily explains why there are two different ths in the document. Also, you absolutely cannot fake on a computer the unevenness of typing, including the way the platen could slip on a letter, then go back to normal, either by itself or with help from the typist; the unevenness of the letters and the differences in ink dispersion, either by filament or cloth ribbons, which depended on the amount of ink left on the ribbon or filament, overstrikes, the amount of copies being made, and the touch of the typist.

All of these documents were obviously done on a typewriter, probably the Executive model.

I do speak from experience, having been an expert typist from the age of 17. I am now 63 yrs. old, and have used all of the typewriters in question.