IF you are DL or COmair employee, you may list and nonrev on any NW or NWLink airline including Mesaba, Chatauqua flights(.

You are supposed to get a paper ticket from DL counter and be listed based on time of listing to secure your seniority. If you list on same flight before I do, you are senior to me (assuming you don't have 21 yrs?) We use some odd code, I can't recall what it is, but it's on the program details (6P-somethng?)
You can only hop on IF you have a paper ticket--if you plan in advance. You are not required to list on the phone--even tho it says that--I asked NW agent and she said as long as you have tkt (she can't give you one) you can do that.
Keep in mind, we displace their buddy pass riders and they do the same to ours.