You are right about the written rule on the carry on but I would say everytime I went through boarding with colleagues they had carryons on cheapest fares and as gold they waived them through. I got there with my carry on and back pack and got hitched to pay. Every single time I was told when you hit *gold you are good. I am talking easy twenty flights with the low fares although I admit that half the time the agent did not care and let me through.