"The name and Aeroplan number of the top tier member appear on the certificate. They can only be used by the member or a companion travelling on the same flight."
So, to confirm then, if travelling on a reservation for two, of which one individual is a top tier member, only one of the pair will be upgraded using a cert? I had been under the impression that both the top tier member and his/her companion could be upgraded with one cert. If my impressions were false and the former is true, then can a top-tier member use two certs on a flight: one cert to upgrade him/herself and the other cert to upgrade his/her companion?