An opponent suggested "Mrs. Peacock in the Billiard Room with the Wrench" and my wife showed him a card. The next player suggested "Mrs. Peacock in the Billiard Room with the Pipe" and my wife didn't have any of them. If you were paying attention, you would know that my wife has the Wrench even though she didn't reveal it.
Nice review, but I have a question: what if you know for sure that all of the other players are aware of this information? That is, they all have good record-keeping systems, such that the two suggestions don't even have to be in consecutive turns, but could be half an hour apart! Any good Clue player will have a system which will enable him/her to know this kind of stuff. So how do you gain a strategic advantage beyond the basic record-keeping? That's the real skill in Clue, and why it is a great game.