It would be a game-changer, as everyone in Washington likes to say these days. It would circumvent a White House bent on circumventing, and it brings a new level of expertise to a beat that's gone a little stale. As Cox pointed out, when was the last time a major political story was broken by a White House correspondent? Even Watergate was uncovered by the Metro desk at the Post.
Best of all, abolishing the White House press corps in favor of rotating correspondents who couldn't care less about the administration's daily political script would benefit voters. Rather than having to rely on White House-created videos, blogs, and photos from a single partisan source, we could have the benefit of tough questions from a variety of reporters representing outlets who specialize in their subjects.
Better for voters, better accountability in politics, and better journalism. Best of all, better for democracy.