The following exercise is inspired by the game Taboo.
Pair everyone off, giving one member of the pair a card that tells them something they must describe so that the other person will guess what it is. Include a list of taboo words that prevent them from going up the lattice, forcing them to be more specific in their descriptions.
e.g. New York Yankees Taboo words: “Yankees,” “New York,” “NYC,” “Baseball,” “Sport,” “National Pastime”
The description giver has to be more specific, saying something like “a collection of athletes, including Derek Jeter and Alex Rodriguez, which strives to beat the opponent by hitting a ball with a bat to score more runs.”
Repeat this as many times as possible, switching roles regularly. A competitive element can be added to the game by offering a prize to the pair that performs best in the exercise. Measuring by the time between the start of the description and a correct guess, with lowest cumulative total over all the rounds winning, encourages an efficient description. Allowing only one guess per clue and measuring by number of guesses encourages thoroughness, though perhaps at the cost of efficiency.
I think this is a fantastic idea, with a patch that is much easier than those suggested by the other responses. Simply tell everyone that for the purposes of this exercise, only that information directly presented in the example is to be considered. People sometimes overlook relevant information or clever third options, and these situations are to be judged only based on the data being considered by the hypothetical person in the given scenario.
If there is any concern about this set up encouraging people to think about things with an insufficient amount of thoroughness, you can save some time at the end for a just-for-fun period where everyone gets to offer their clever workarounds and extra information that would have changed what the proper decision was, had it been considered.