Here's one that was a surprise to me.

I recently used the Companion Certs issued by Amex and CIBC Aerogold. As I am sure most of you know, you have to pay full fare Y or J in order to get the "free" ticket. What I didn't know is that the full fare ticket does not get the Y or J class of service bonus as both the full fare ticket and the companion ticket are booked in B (if you paid Y fare) or C (if you paid J fare).

When I called to ask about it, the agent said that it was very clear that both tickets were to be booked in the lower class. Does anyone have a cert handy to see if this is printed on the cert?