>>Proportional Spacing Is Not Kerning. Kerning does make use of Proportional Spacing.<<
You are sort of right — for example look at the word “Ward.” Kerning to make it look correct would tuck the “a” under the right upper “leg” of the “W” In addition, the designer may decide to tuck it to the left a little more (that is manual kerning) to make it visually pleasing. Likewise, the “r” might look like it is now not even part of the word so it might be manually kerned to the left a tiny bit to visually associate it back to the original word.
I owned and operated a Compugraphic Typesetter for several years (before Windows 3.x) and we had to interpret kerning codes and sort of “guess” what the result would be. And the film was EXPENSIVE! A miss could easily cost 10 or 20 bucks. Do that 5 or 6 times a day and it could get into some money.
To say it was great was to say the least. That machine could pack letters like nobody's business. ABA Journal article said there was a 40% reduction in space needed for any given article.
For kerning (as I recall) you selected a FONT with kerning or a FONT without kerning. It was pretty locked in so you couldn't take just any old font and turn it on and off like you can with Microsoft Word.
Another feature it had was compressing rows.
I see no sign whatsoever that anything approaching the power of a Wang photocomposition machine was used to produce the document in question. Folks who imagine the forgers (if they exist) sitting down at a common WP and doing the job are simply unaware of how utterly adanced photocomposition was 33 years ago.
That's smallscale stuff. You get into your major linetype machines using hot lead, all things were possible ~ but I really don't get the feeling the document in question was produced by hot lead.
We are getting spoiled by our computers. We think of what they can do and imagine it couldn't have been by other means. At the same time we look at an ancient product and say "hey, they couldn't do that", but they did do that.
BTW, I think the Wang machine was the first photocomposition device to use an extended memory cache of some kind in an off-line mode. It wasn't hooked up to an IBM main frame system as a dumb terminal ~