I just checked quite a few examples. The "Ka" in the address field and the "Ke" in "Kenya" show the "K" striking perhaps a pixel above the following lower case letter. The "K" in "Kansas" is very high.
In fact, it appears to be the rule rather than the exception that an upper case letter followed by a lower case letter will strike slightly high. This effect would tend toward straightening out a curve at the edge of the document.
I took that into consideration and looked at the average drop for the word and the drop of the baseline of the letter itself. Even if the letter bar struck high it should still have struck somewhat parallel to the horizontal line of the platten, not curving down to follow later line of a bend caused by a book binding. Ergo, the typewriter line of print should be consistently horizontal across the page, as is the offset printed ink on the page. Why then is there ANY discrepancy in parallax at the same vertical vector between the printed and typewritten ink on the page?
I understand why the background safety paper pattern continues in a straight line without curving back... It's merely the laser paper the image is supposedly printed on (although in this instance, it too, is just one of the layers)... but both parallel lines of print should follow the same curved surface plane of the perspective the folio page follows back to the binding. They don't quite. Smoking gun.