Help me understand Hypothetical Questions

I think I’m nearing the limits of what I can do by tweaking Automated Testing by Roger Carbol. What I really want is a bit different - a “programmable skein” that is written into the game’s source, following the skein’s node model rather than a bunch of flat tables. But to avoid the problems that Automated Testing encounters, I think I need to use Hypothetical Questions, which is a baffling bit of code if I ever saw one. Where are these fancy memory-mashing features (like “protect”) documented?

Here. The Glulx Specification is a handy file if you plan on low-level Glulx hacking.