It’s not sorcery tech at all. Nothing in their “goblin post mortem” is surprising the least bit if you have a working high-level mental model of what an LLM is.
It’s a fancy autocomplete that takes a bunch of text in and produces the most “likely” continuation for the source text “at once and in full”. So when you add to the source text something like: “You’re an edgy nerd”, it’s very much not surprising that the responses start referencing D&D tropes.
If you then use those outputs to train your base models further it’s not at all surprising that the “likely” continuations said models end up producing also start including D&D tropes because you just elevated those types of responses from “niche” to “not niche”.
The post-mortem is hilarious in that sense. “Oh, the goblin references only come up for ‘Nerdy’ prompt”. No shit.