I know this was just a harmless typo, and this is not intended as an attack, but I found the idea of a "casual" decision theory hilarious.

Then I noticed that that actually explains a great deal. Humans really do make decisions in a way that could be called casual, because we have limited time and resources and will therefore often just say 'meh, sounds about right' and go with it instead of calculating the optimal choice. So, in essence 'causal decision theory' + 'human heuristics and biases' = 'casual decision theory'