They do need Beast. They can win without him, but they do need him. They feed off of this man's personality. Even if he has 20 carries for 50 yards, they will be 50 tough yards. And the threat of him will always be there. C-Mike has filled in very admirably, and I think it's awesome that he's back in a Hawks uniform and possibly a part of our future. But having Beast has more ramifications than what happens on the field. He's the attitude, and at times the heart beat of this team, and I don't think that should ever be discounted.
Hell, they'll win if for him just so he can keep playing.