Hmmm...
Having been an enlisted man in the Army, let me assure you that some very talented people found themselves doing jobs very much below their highest capabilities.
Military life is not always fair. Some people get too much work and others get too little. When you get too little, sometimes a superior supplies more. Sometimes you get dismissed early instead. It was an art being able to predict which would be the case.
A clerk-typist might either tell his superior that he had too little to do, or he might figure out ahead of time the exact spacing required to center the unit's letter head. Once the numbers had been worked out the first time there would be no need to do it again.
The observation above, however, that the memo exhibits "kerning", that is that letter spacing is a function of specific adjacent letters, is, as has been stated, beyond the capabilities of the equipment available at the time.
First, thank you for your service! I was born and raised in the USAF, and have been married to an active duty USAF member for the past 17 years. I've never been active duty, but I DO know how military life can be unfair! I wouldn't trade my upbringing or current situation for the WORLD, though. It's a proud life! My point was, though, that I sincerely doubt whoever typed that would have taken the time to consider the size of each and every individual space and letter when centering the ADDRESS on this memo. You make a good point, though, that once he did it...it could just be re-used over and over. I just thought it was funny that there was so much attention to the centering on the memo, rather than the other odd things.