It likely did. The Executive Selectric had an interchangeable ball, rather than hammers, that struck the paper. These balls representented the different fonts.
Some offices had ten or twelve different balls.
Some offices had ten or twelve different balls
True, but what would make it proportionate was the amount the carriage moved from letter to letter. I don't know that the Selectric was that sophisticated.
Speaking to the point made upthread, about how detectives could tell which typewriter could have typed a certain memo based on the crud build-up in the keys, this was also true with the Selectrics. Back in the late 70's, early 80's, I remember many a time cleaning the balls of my typewriter (STOP snickering you guys!!!) You used a clay-type material that you would press into the letters on the ball, and work it around to clean the whole thing. The wad of cleaner would end up being this really gross grey color. This was before the newer single-use ribbons.
I also remember taking a razor blade to scrape the carbon off the copy for mistakes, in order to fix them on both the original and the copy. It never came cleanly off, always was a little bit messed up.
My typing teacher in high school (remember them??) used to make us roll a sheet of paper in, type a few words, take the paper completely out, and then put it back in and edit one word. It took some doing, let me tell you, but we became experts at fixing typos.
I located this on the link shown. So the memos didn't come from an IBM Selectric.
IBM Selectric"> eliminated the jams that affected earlier designs of electric typewriter. The typeball design had many advantages, especially in eliminating of "jams" when more than one key was struck at once, and in the ability to change the typeball, allowing multiple fonts to be used in a single document. Selectric mechanisms were widely incorporated into computer terminals in the 1970s, because the typing mechanism was fast and jam-free; could be initiated by a short, low-force mechanical action; and did not require the movement of a heavy "type basket" in order to shift between lower- and upper-case.
Later models of Selectrics replaced inked fabric ribbons with "carbon film" ribbons that had a dry black or colored powder on a "once-thru" clear plastic tape. These could be used only once but they were in a cartridge that was simple to replace. They also introduced auto-correction, where a sticky tape in front of the print ribbon could remove the black-powdered image of a typed character, and introduced selectable "pitch" so that the typewriter could be switched among pica ("10 pitch"), elite ("12 pitch"), and sometimes agate ("15 pitch"), even in one document. Even so, all Selectrics were monospaced -- each and every character was the same width. Although IBM had produced a successful typebar-based machine, the IBM Executive, with proportional spacing, no proportionally-spaced Selectric office typewriter was ever introduced. There was, however, a much more expensive proportionally-spaced machine called the Selectric Composer which was considered a typesetting machine rather than a typewriter.
http://www.nationmaster.com/encyclopedia/typewriter