What I kept bouncing off of was all the stupid as shit "sally sends a BUY message to Tommy's bagel shop" crap. I just needed about two to four pages worth of text & diagrams demonstrating how objects and structs are pretty much the same thing, and what the OO sugar inheritance and keywords and dynamic dispatch and such do under the hood, which ain't that complicated. Every single book I picked up (back in the '90s, when if you didn't know someone to personally recommend a book it was much harder to figure out which ones were decent and which sucked) wanted to use those awful, cutesy analogies to introduce OO and they just confused the hell out of me, and convinced me something dead-simple was hard.