Picking up an old text book

Yesterday I took a look at a textbook I have had ever since I took a course in 1972-1973. The book was published in 1969 so it is 50 years old now and is titled "Computer Organization and Programming" by Professor Charles William Gear. Professor Gear is still around; currently at Princeton.
The book does not look very worn; no marks or writing or even food stains.
I read a little bit of it yesterday. Well written, fascinating and requiring more focus and attention than I am likely able to provide at this age.
Why is my copy so pristine?
It was the assigned text for Computer Science 202 a course taught at York University by Professor Frieder Schwenkel. That was his last year at York; he was appointed a Professor at the University of Hamburg in 1973 and passed away in 2012.
Neither I nor my classmates really looked into the book very much when we took the course. Professor Schwenkel's
attention was focused on an Interdate 70 16 bit mini-computer that resided in a room across the hall on the 6th floor of the Ross Building from his office. For reasons good or bad he decided to have us learn about it.
In some ways it was a good choice that made for a fascinating course, especially for me. The Interdata 70 was a half word machine with many of the same instructions as an IBM mainframe cut down to 16 bits. Picking up how to program it in assembly language was not that difficult and we learned quickly how to work with a machine in hands on fashion.
Professor Schwenkel was pretty flexible about we did and at one point he offered me the chance to work on some of the CS408 projects. The one that intrigued me was the development of an interpreter to execute programs written for another computer. I never did program it then but did some work in the area later on.
In the meantime there were some practical problems to solve.
One thing I learned from the course was that you could never totally trust the documentation that came with computers. The machine had shown up with a teletype machine with paper tape as the primary input system but at some point a floppy disk (8 inch size) drive showed up. It was run through an auxiliary processor which Interdata termed a channel (just as IBM did). Only problem, it didn't work the way the documentation said it would. Much scope for endless experimentation the need for which got me a prized key to the machine room for 24 hour access.
Now as I glance at Professor Gear's book I wonder if I would have benefited from a course more focused on its concepts. Certainly I would have approached programming from a more principled and academic foundation as opposed to figuring things out from first principles.
Maybe I should read the book although it does seem a little quaint with flowcharts and program examples written in Fortran. Flowcharts I never bothered with unless an assignment required one but I can sort of still read Fortran and it might challenge my brain a little. And, help me justify having kept the book for 47 years although keeping books around never needed much encouragement for me.