I'll hopefully help save you guys some trouble:

CO will *NOT* combine travel certificates. The way it was explained to me is that every certificate is issued against a flight or problem. This is so they can associate a dollar amount against a problem/flight. So by combining these items in to one certificate they loose the ability to track that information. This makes sense in the business world as at the end of the day you want to know what you did well and what you didn't.

In addition, you can not combine a travel certificate with your CO Travel Bank/Travel Club money. I also tried to accomplish this feat.

You can only use one certificate per flight. The women I spoke to in executive customer service equated this to going grocery shopping where you can only use one coupon per item, you can't stack them (as the fat wallet guys like to call it).

My response to that was: Well, in this case, I happen to have a store credit and a coupon. Logic would dictate that I could use both which is normally the case.

I was then told that I was incorrect.

Essentially the only way to do this is to "wash" your tickets. By this I mean if you travel enough, next time you go, use the second benefit for that flight. For those that are not loyal to one airline this won't be an easy task to accomplish quickly but you get the same net benefit in the end.

-Alex