Then came the caveat; I bought this damned pamphlet on Seduction, used it, and now the merchant didn't save my purchase records like any other bookseller! I didn't expect him to suggest other grimoires I might enjoy based on my interest, but come on! I am aware that I can burn through some shards to summon each of my demons to check at the trainer, but what a waste! There had to be an easier way.
Then I discovered Grimoire Keeper, an addon that aids budding demon-wranglers in remembering which abilities, and ranks thereof, their demons already have. Keep reading to discover it for yourself. Grimoire Keeper is a great tool for tracking demon training. The author who wrote this one also developed Recipe Book, which is another addon that remembers things for you. (Future Addon Spotlight love!?) I thought the description for Grimoire Keeper was fantastic, so I thought I'd post it. Here it is in the developer's own words:
"When you summon a demon, Grimoire Keeper's tiny little gnomes will interrogate it using top-secret techniques to learn its level of mastery for all spells. They'll then write down that information for that character, storing it securely in your per-character SavedVariables file. Any time your demon learns a new spell, our gnomes will re-interrogate it for added thoroughness.
When you visit the demon trainer, the gnomes will spring into action, bustling up to the interface panel with BLUE CRAYONS to color all the books that your demons know blue. Books you can't learn yet will remain red, which leaves you, the fortunate warlock, to select which of the white books you'd like to buy.
If you can't summon a Felguard yet, they also color the Felguard grimoires with BLACK CRAYONS so you're not duped into buying one of those.
Don't worry, the crayon washes off before the next person tries to buy anything. No property is permanently damaged."
Once you've installed this addon, you will need to summon each of your demons, so the "magic gnomes" can study then, thereby remembering what abilities you've already trained. After that, you're free to visit the demon trainers and Grimoire Keeper will function. That's it, no configuration required. With that in mind, I can't really give you any tips on how to use it.
If you play a Warlock, this is one of the solutions to your demon-training problems at your disposal. Download it, install it and go back to rolling your face on the keyboard. Dismissed!