If CO's business model were superior, why weren't other carriers clammoring to join up and be like CO?

The fact of the matter is that CO's business model worked well to get it to where it is today. From a mickey mouse joke of airline 15 years ago to a solid, respectable player today. Those of us who were around back in the "meatball" days remember -- CO was a real joke. Ok, we've overcome that now. But what's next? Organic growth is not going to cut it, and CO clearly sees that.

They need partners to get feed and network growth faster. So do they play along with the behemoth that is now DL, all while DL has revenue sharing agreements with AF/KL? Why would they let CO in on that?

Meanwhile, take a carrier like UA with a more successful loyalty program (MP is even bigger than AAdvantage, despite AA being the larger carrier) as well as existing Alliance experience with revenue sharing (e.g., with LH presently) that CO does not have. UA is now smaller than DL and AA, so they have a motive to partner up with someone. What does CO bring to the table? Its planes and hubs, really. They have a reputation for reliability and cleanliness (and maybe the free food in Y), but other than that, there's nothing special about them. And as we've discussed many times on this board, procedurally, they could learn a bit from someone else.

Just look at the fare class changes they did in the past couple weeks -- all to get in line with Star Alliance fare classes. SkyTeam never even thought of mandating that (and think of all the difficulty CO agents have keeping track of that alphabet soup -- I have many times had to educate them about the various classes on carriers they get confused on). While the weekend's upgrade was a bit of effort, it will pay off in the long run with ease of booking partner fares (e.g., RTW fares) and awards.

For the most part, the carriers will run independently. US charges for drinks (so does SAS intra-Scandinavia), UA has E+, LH has its F-class terminal in FRA that nobody else can use, etc. etc. etc. So I wouldn't worry too much about CO losing its flavor. CO will still be CO.

But saying that CO has nothing to learn from all this is a bit shortsighted, IMO.