I think that goes into the category of speculation - there are a lot of cons to such a merger. Also, Heathrowguy is probably right - so long as NW exists its 'super voting' share - not to mention the partnership contracts from when NW invested in CO* - could stand in the way of CO doing any mergers.

* Hard to believe but true - there was a time when NW was the one with the money helping CO out - now look at things....