A related trick, especially if you are flying somewhere unusual, is to have the airport code handy. I recently flew YVR-LHR-RUH (Riyadh, Saudi Arabia) on BA using CP points. The agent did not know how to spell Riyadh, or even where it was, so I just offered the airport code, for which she was grateful. However, I guess she just figured if it's BA, it must be Europe. I got a 1st class ticket from Vancouver to the Middle East, for 100,000, instead of the "normally" required 125,000.

It pays to be more knowledgable than the agent, about all sorts of things.

Ken