I didn't watch the show carefully enough to know the answer to this: what would happen if, after Bob posed a question such as this, the first spouse queried not only knew what the term meant but explained it in the course of giving their predicted answer? (Probably he'd been directed in advance, "Start the questioning with Couple #3, because they're idiots.")
My own observation would suggest your first scenario of a contestant explaining the question in their answer would be impossibly rare to begin with. A typical player response: "I'd say spaghetti, because she's always making it," not "I'd say linguine because that is a type of noodle, which is what you asked me." That, and I've seen these types of questions where the first spouse or two understood it, and the third or fourth would still give a nonsensical answer confidently.
Beyond that, I think the show knows/knew the risks of asking those questions to begin with, which still play legitimately when everybody understands them. But even if the first half of each couple understood, they always had a chance the contestants in isolation could find their gold.
-Jason
