What exactly is it? I get the sense it's basically a knowledge graph and an inference engine. But what was it actually doing in terms of submitting queries and spitting out takeaways in human readable form?

I'm extremely skeptical about the anecdotes about the game as an indicator of this thing's competence. It sounds unlikely that this thing actually encoded any sort of game state or nuanced simulations and was really just spitballing on vague strategies that just happened to find some cheese (twice?). I'm guessing they had to play the strats until one of them proved valuable, and it's kind of weird and surprising that they thought this was a good use of their time and model.