Sometimes grimoires obscure things with secret codes or don’t explain certain steps because logically someone at the time would have known how to do what was a common action of the day. But sometimes they’re cryptic and mum on the actual meaning of certain designs and symbols for seemingly no reason. But I think the reason is simply: magicians.
To go into further explanation and not be so cryptic: I just wrote down a spell in one of my journals, and where a couple of components would go that could be changed and customized depending on need, I just left brackets there with nothing inside them, to let myself know that the chunk is swappable, it’s a variable. In another part I drew a dashed diagram with arrows and no other explanation–it’s the instructions for a certain hand-motion to make at the end of the spell.
There are no full explanations written down simply because I’ll know what I mean, and when I thought about that at the end, I said: “fuck it, it’s my book, if someone finds it when I’m dead it’s not like the book is for them.” And that’s the explanation behind a ton of crypticness: in the end, a lot of these books are made for personal usage or would come with an oral tradition where one person would explain it to another. If you’re not that person or not in that oral tradition, then what’s written there isn’t for you to understand, and cracking it open is going to require intuition, divination, outright necromancy (throttling the author’s ghost for the answer), or just making something up and seeing if it works. It’s not really on every magic-user to write a personal magic book that will be perfectly instructive to people born generations after they die. It’s on us to try to figure out their cryptic bullshit anyway.
(…I should print out this post and attach it to my Will.)