Wow, what a blast from the past. I remember gazing at the data book as a kid[+], wondering what sort of super genius came up with some of those bizarre operations and wondering when I'd learn enough / be smart enough to want to use them all.

Never did get around to figuring it out and now I don't have to!

[+] Once upon a time you could write to TI, National etc and they would send you data sheets and even whole databooks for free. (I think I remember buying a set of TI TTL datebooks at a junk shop, but I think National or Linear would send theirs for free). Since I had to pay for parts out of my pocket money there was a lot of pouring over designs before getting parts and trying to build anything. I guess this is the equivalent of the folks who had to submit card decks once a day.