A two-night team would work for ABC, whereas I think it's a bit of an issue for CBS, but I'll get to that in a moment. Muir's weekend role had been more prominent than just about any of his predecessors, which made him a de facto #2 or #3 at the network (a position always teetering back and forth between him and George behind Diane), much like George was during the Gibson-led era with Diane. Building up David's profile made his ascension to the weekday desk less surprising; we figured he'd be promoted, but we weren't totally sure how. Declaring a sole weekend anchor could give some the impression that they're trying to build another personality into the top-tier anchor. Say what you will about the reporting core at ABC, the depth they have in anchor personnel is pretty impressive and versatile. As for CBS, they could stand to build up another anchor, even if not for the long-term. Jim Axelrod's okay, but I have thought on many occasions that Jeff Glor could easily be developed like Muir was across town.