The manuals for those systems were quite interesting.
If you had a question, you could read the manual and swear that the manual did not answer the question.
Once you figured out the answer by some other means, if you went back to the manual and read it carefully you would discover that it actually did answer the question precisely.
I don’t think it was just me. Several of the people that I worked with on that project reported the same thing.
I really enjoyed working on the 16 bit mini computers from Texas Instruments. They were a lot of fun.
For another era of stuff that I used growing up, PCs were by then complex enough (286/386/486 era) and/or commoditized enough that the systems weren't well documented.
[1] https://archive.org/details/HiddenPowersOfTheTrs80Model100